FAQ
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Aa. Check whether the HDMI cable from the interactive display is properly connected to the graphics card of the connected PC. Disconnect and reconnect the HDMI cable securely.
b. On the interactive display, go to Home → Android → Settings → Advanced Settings → Input & Output → Advanced HDMI Settings and set the connected HDMI input to 1.4.
(Menu paths may vary by model.)
• NN Model: Tap the left/right arrows in the center of the screen → Open the sidebar → Tap the second icon from the bottom (三) → Select HDMI under Shortcut Tools → Set HDMI to 1.4.
• NB/NA Model: Main Screen → Settings → Input/Output Settings → Set EDID to 1.4.
• ND Model: Main Screen → Settings → Input/Output Settings → Set HDMI to 1.4
(ND8600, ND86ZL, NA86AN, ND86ZG)
• AL Model: Switch to the external input → Tap the left/right arrows in the center of the screen → Tap the Monitor Settings (三) icon at the bottom of the sidebar → Scroll down in the displayed window → Set EDID to 1.4.
• ID Model: Tap the left/right arrows in the center of the screen → Tap the diamond-shaped icon in the center of the sidebar → Select the center square image tab → Set HDMI EDID Version to 1.4.
• IB Model: Tap the left/right arrows on the screen → Tap the second icon from the bottom (三) on the sidebar → Input Signal Status Settings → Advanced → Set HDMI Version to 1.4.
• IG Model: Swipe up from the bottom of the screen to display the menu bar → Settings → Settings → Set HDMI EDID to 1.4.
• KCQ Model: Settings → Advanced Settings → Input & Output → HDMI Settings → Advanced HDMI Settings → Select the desired HDMI input (HDMI 1–4) → Set HDMI to 1.4.
c. In Windows, go to Display Settings → Advanced display and lower the Refresh rate for the selected display.
d. If you are using a splitter, connect the HDMI cable from the interactive display directly to the PC graphics card, bypassing the splitter, and check whether the display works.
If the cable is defective, please contact Combus Tech Customer Support to request A/S service. -
Aa. Check whether the USB touch cable is connected to the PC you are using.
• Touch functionality is not available if the USB cable between the interactive display and the PC is not connected.
• If there is no disconnected USB cable on the back of the desktop PC, disconnect and reconnect all connected USB cables. Then restart Windows and try again.
b. Tablet PC Settings
1. On the PC, go to Control Panel → Tablet PC Settings → Settings.
2. When a white screen appears on all connected monitors, press the Enter key until the message “To identify the touch screen as a tablet PC screen…” appears on the interactive display.
3. While the message is displayed on the interactive display, touch the interactive display screen directly with your finger.
4. Press the ESC key to exit the screen setup. -
Aa. If the batteries in the remote control are depleted, it may not function properly. Replace the batteries and try again.
b. Communication between the interactive display and the remote control uses an IR sensor. Point the remote control directly toward the sensor located at the bottom of the interactive display frame, and try again. -
Aa. Check whether both the device you are trying to connect and the interactive display are connected to the same Wi-Fi network.
b. Check the Wi-Fi network environment you are trying to connect to.
• Screen mirroring can only be established when the IP subnet of both devices is exactly the same.
• If a separate wireless AP (Access Point) is installed in each classroom, the SSID (Wi-Fi name) for each classroom should also be clearly separated.
Ex) Class 1-1: Wi-Fi 1 / Class 1-2: Wi-Fi 2
• If the Wi-Fi names are not separated in an environment like the one described above, the devices may connect to signals from different wireless APs. In this case, screen mirroring may be unavailable. -
Aa. Check the Wi-Fi password again to make sure it has been entered correctly.
• If the password is incorrect, “Saved” will be displayed next to the Wi-Fi network in the Wi-Fi list. When the connection is successful, “Connected” will be displayed.
b. Completely shut down and reboot the product, then try connecting again.
• This may be a temporary issue. Press and hold the Power button to completely shut down the product, reboot it, and then try connecting to Wi-Fi again.
c. Check whether the wireless dongle (wireless LAN adapter) is properly installed. -
AIf the product remains running for an extended period, heat and system load may build up due to the characteristics of electronic devices, which can cause the product to slow down or freeze.
When the product is not in use, press and hold the Power button to completely shut down the product.
If the issue persists, try performing a Factory Reset on the product. -
AThis may be a temporary issue caused by product overheating or a software conflict. Try completely shutting down and rebooting the product by disconnecting and reconnecting the power cord from the electrical outlet connected to the product.
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Aa. Check whether the power cord is properly connected to the power outlet.
b. For models that use an AC adapter, disconnect the AC adapter and clean the contact terminals. Then reconnect it and try turning the product on again.
>> Check that the power cable is properly connected, then reconnect it securely.
>> Check whether the main power switch located in the center of the back of the interactive display is set to “On.” -
Aa. Check whether the set-top box located on the side of the interactive display is powered on.
b. Check whether the external input source is switched to the HDMI input connected to the set-top box, such as HDMI 1 or HDMI 2.
c. In the set-top box settings, run Auto Channel Search again to search for available channels. -
ACheck whether the Brightness setting or Power Saving Mode is enabled using the remote control or in the Settings menu.
The issue may also be related to the backlight lifespan. If the problem persists, the product may require inspection.
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AIf you have connected an HDMI cable to the HDMI OUT port, press the Home button to access Android mode. If the Android screen is displayed on the device connected to the HDMI OUT port, please adjust the settings as follows:
Home → Settings (Display Settings icon) → Input/Output → Enable HDMI IN/OUT
If the screen is not displayed through the HDMI OUT port only when switching the input source to HDMI, enabling the setting above should resolve the issue. -
AQ: I connected a PC to the interactive display, but the screen keeps flickering or the “No Signal” message appears briefly and then disappears. What should I do?
A: This issue is mainly caused by signal compatibility between HDMI 2.0, the connected HDMI cable, and the PC’s graphics card. You can try changing the interactive display’s EDID version to 1.4 to improve signal stability.
■ How to Change the HDMI EDID Version
1. Open the Side Menu Bar
Open the [Side Menu Bar] from the left or right edge of the screen.
2. Open Settings
Tap [Settings (gear icon)] from the menu.
3. Go to the Input/Display Settings
From the Settings menu, select [Monitor], [Input], or [HDMI Settings], depending on the model.
4. Change the EDID Version
Find [HDMI EDID Version] and change the current setting from [HDMI 2.0] to [HDMI 1.4].
5. Check the Connection
After changing the setting, the screen may briefly reconnect. Check whether the flickering has stopped and the signal remains stable.
※ Why Should I Change the EDID Version?
HDMI 2.0:
Supports 4K resolution and higher refresh rates. However, signal attenuation may occur with long HDMI cables (5 m or longer) or low-quality cables, which can cause screen flickering.
HDMI 1.4:
Provides lower bandwidth than HDMI 2.0, but generally offers more stable signal transmission over longer distances and better compatibility with older devices. For typical classroom or meeting environments, HDMI 1.4 is usually sufficient for a stable display.
⚠️ Additional Troubleshooting
Replace the HDMI Cable:
If the issue persists after changing the EDID version, the HDMI cable itself may be faulty. Try replacing it with a certified HDMI 2.0 or higher cable.
Try to connect different HDMI Port:
Connect the PC to another HDMI port on the back or side of the interactive display and test the connection again.
Check the Resolution and Refresh Rate:
In the PC’s display settings, make sure the refresh rate is set to 60 Hz. -
AQ: The touch response is slow when writing or clicking icons. Is there a way to improve it?
A: If the electronic whiteboard’s picture enhancement feature, [Movie Mode (MEMC)], is turned on, a slight delay (Input Lag) may occur due to the processing required to make the screen appear smoother. When writing on the board or performing quick operations, it is recommended to set this feature to [OFF].
■ How to Resolve Touch Delay (Disable MEMC)
Open the Menu: Press the [Menu] button on the remote control or open the main menu on the screen.
Go to Picture Settings: Select [Picture] (or the Video/Picture Quality settings) from the menu.
Find Movie Mode: In the submenu, look for [Movie Mode]. Depending on the model, it may be labeled MEMC.
Change the Setting: Set the feature to [OFF] (or turn it off).
Check the Touch Response: Close the menu and try writing on the screen to see whether the touch response has improved in real time.
※ What Is MEMC (Movie Mode)?
Function: MEMC is a technology that makes low-frame-rate video appear smoother by artificially inserting interpolated frames between existing frames.
Effect: It provides smoother images when watching movies or sports, but it can cause a slight delay during real-time operations such as writing or touch control because of the additional processing time.
Recommended Setting: ON when watching videos; OFF during regular classes or meetings, especially when using the whiteboard for writing.
⚠️ Additional Checks
When connected to a PC:
If you are using a laptop or PC connected to the electronic whiteboard, please check the PC’s display settings and make sure the refresh rate is set to 60 Hz. If it is set to 30 Hz, the touch response may feel significantly slower.
Clean the sensors:
Dust or foreign particles on the touch sensors around the bezel of the electronic whiteboard can also cause delayed touch recognition. Please gently clean the bezel with a soft cloth. -
AQ: The pen thickness suddenly changes or the color switches while I am writing. Can I lock the settings?
A: This happens when Multi-Pen Mode is enabled. This feature is designed to allow multiple people to write on the board simultaneously or to recognize different parts of the pen (such as the front and back) or different pen thicknesses separately. If you are writing alone and want to maintain a consistent pen thickness, please set this feature to [OFF].
■ How to Resolve the Issue (Disable Multi-Pen Mode)
Open the Side Menu Bar: Open the [Side Menu Bar] located along the left or right edge of the screen.
Open Settings: Tap [Settings] (the gear icon) in the menu.
Change the Option: Find [Multi-Pen Mode] in the settings list and set it to [OFF] (or Disabled).
Check the Result: Now, check whether the selected pen color and thickness remain unchanged even if your palm touches the screen or the angle of the pen changes while writing.
※ Why Does This Happen?
Multi-Pen Mode ON: The electronic whiteboard analyzes the contact area in detail and recognizes a thin pen, thick pen, finger, and other inputs as different tools. If the side of your hand touches or brushes against the screen while writing, the whiteboard may mistakenly recognize it as a thick pen and automatically change the pen settings.
Multi-Pen Mode OFF: Regardless of which input tool touches the screen, the whiteboard uses only the currently selected pen settings. This is the recommended setting for stable, single-user writing. -
AQ: I don't want the electronic whiteboard to boot up automatically when I plug in the power cord or turn on connected devices. How can I change this setting?
A: If Auto Start Mode is enabled in the electronic whiteboard's settings, the device detects a power signal and turns on automatically. Please follow the steps below to disable this feature.
■ How to Disable Auto Start Mode (System Settings)
Open the Side Menu Bar: Open the [Side Menu Bar (Quick Menu)] located along the left or right edge of the screen.
Open Settings: Tap [Settings] (the gear icon) in the menu.
Go to Monitor Settings: In the settings list, select the option related to [Monitor] or [Display].
Change the Option: Find [Auto Start Mode] and change the setting to [Disabled].
Complete the Setup: Close the settings window and check that the device only turns on when you press the power button manually. -
AQ: The password I set for the lock screen is not working. What is the default password or administrator master password?
A: First, try the factory default password 0000. If you previously changed the password and have forgotten it, you can reset the password by entering the master password.
■ How to Unlock and Reset the Password
Try the Default Password: First, enter [ 0 0 0 0 ] and check whether the lock screen is unlocked.
(This applies if the password has never been changed.)
Enter the Master Password: If the default password does not work, enter the following combination of letters and numbers in the input field on the current lock screen. Be sure to enter it with the correct capitalization.
Master Password: IFP22011!!
Open the Reset Screen: Once the master password has been entered correctly, the password reset screen will automatically appear.
Set a New Password: Enter the new password you would like to use and complete the setup.
⚠️ Important Notes When Entering the Password
Case Sensitive: The master password is case-sensitive. Make sure to enter uppercase and lowercase letters correctly.
Check the Keyboard: Before entering the password, check the language/input mode of the on-screen virtual keyboard or any connected physical keyboard to make sure it is set correctly. -
AQ: A lock icon appears on the screen, or the touch function does not work at all. How can I unlock it?
A: You can easily disable the touch lock using a combination of buttons on the remote control. The most important point is to make sure you are pointing the remote control in the correct direction.
■ Method 1. Unlock Using the Remote Control Button Combination (Recommended)
Check the Receiver Direction: Point the remote control directly at the remote control receiver (sensor) located at the bottom-left corner of the electronic whiteboard when viewed from the front.
Enter the Command: Press the following buttons in sequence at a steady, rhythmic pace:
[Volume − (Minus)] 2 times → [Volume + (Plus)] 2 times
Repeat and Check: After entering the sequence, the touch lock should be disabled immediately. If it does not work the first time, point the remote control directly at the receiver and try the sequence again.
■ Method 2. Forced Unlock Using a USB Drive (If the Remote Control Does Not Work)
If the remote control cannot be used or the touch lock cannot be disabled due to a software error, you will need a USB drive containing the Child Lock unlock file.
Prepare the File: Copy the provided [usb_child_key] file to the root directory of the USB drive.
(Do not place the file inside a folder.)
Connect the USB Drive: Insert the USB drive into a USB port on the electronic whiteboard while the touch lock is enabled.
Automatic Unlock: Once the system recognizes the unlock key, the touch lock will be disabled automatically without requiring any additional action.
※ Why Is the Bottom-Left Corner Important?
Most electronic whiteboards have the remote control receiver built into the bottom-left corner of the front panel. If you point the remote control toward the center of the board or in the wrong direction, the signal may not be received and the touch lock may not be disabled. Please make sure to aim the remote control directly at the receiver. -
ASwipe inward from the left or right edge of the screen toward the center to open the side menu.
From the side menu, you can quickly access functions such as Back, Home, Recent Apps, and Source Switching. -
AQ: I don't remember my screen lock password or pattern. Is there a way to reset it using the remote control buttons?
A: Yes. You can reset the password with administrator privileges by entering a specific sequence using the volume buttons on the remote control. Please follow the steps below carefully.
■ Password Reset Procedure Using the Volume Button Combination
Check the Password Input Screen: Make sure the password or pattern input screen is currently displayed.
Enter the Remote Control Command: Point the remote control toward the electronic whiteboard's remote control receiver, then enter the following button combination 4 times in total:
[Volume − (Minus)] 2 times → [Volume + (Plus)] 2 times
(Repeat this sequence 4 times consecutively.)
Complete the Reset: If the sequence is entered correctly, the existing password will be deleted and the lock will be disabled.
⚠️ Important Notes
Enter the Sequence Without Long Pauses: If too much time passes between button presses, the sequence may not be recognized. Enter the buttons smoothly and continuously with a steady rhythm.
Check the Remote Control Signal: When pressing the buttons, check whether the electronic whiteboard's LED indicator flashes. This confirms that the remote control signal is being transmitted properly. -
AQ: I want to disable the function that turns on the electronic whiteboard when I plug in the power cord or turn on the PC.
A: This happens when the electronic whiteboard's Boot Mode is set to [Auto]. Change the setting to [Manual Boot] so that the device only turns on when you press the power button manually.
■ How to Change the Boot Mode
Open Settings: Tap [Settings] (the gear icon) from the electronic whiteboard's home screen or menu.
Go to General Settings: Select [General] from the settings list.
Select Boot Mode: Find the [Boot Mode] setting in the submenu.
Change the Setting: Select [Manual Boot When Power Is Connected] (or [Remain in Standby Mode]).
Check the Result: Confirm that the electronic whiteboard remains in standby mode instead of turning on immediately when power is supplied.
※ Changes After Adjusting the Setting
Before: When the power strip is switched on or the connected PC boots up, the electronic whiteboard turns on immediately.
After: When power is supplied, only the red power indicator (standby status) turns on. The screen turns on only when the user manually presses the power button or the remote control.
- Headquarters
- 401–404, Ace High-End Tower 6, 234 Beotkkot-ro, Geumcheon-gu, Seoul, Republic of Korea (Gasan-dong)
- Factory
- 107 Hogokgongdan-ro, Ujeong-eup, Hwaseong-si, Gyeonggi-do, Republic of Korea
- R&D Center
- Room 402, 234 Beotkkot-ro, Geumcheon-gu, Seoul, Republic of Korea (Gasan-dong)
- Tel
- +82-2-6299-5151 [Customer Center: Ext. 1 / Sales: Ext. 2]
- Fax
- +82-2-6299-5158
- Hours
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