LG TV Invalid Format (EASY Fix!)

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Did you connect an external device to your LG device but get the LG TV invalid format error? 

This common error message indicates that your LG TV’s resolution setting is incompatible with the external device connected to the TV. 

A photo of LG TV Invalid Format

Other factors like loose HDMI cables, which will be discussed subsequently in this guide, can trigger the “invalid format” message.

Follow the methods provided here to resolve this issue.

Causes of LG TV Invalid Format Error

You might wonder why the “invalid format” error message popped up on your LG TV screen when connected to an external device. 

The causes are not far-fetched, and one or some of the factors below is the culprit;

  1. Loose or faulty HDMI Cables or ports
  2. Faulty or incompatible resolution setting on your TV or the connected device.
  3. A faulty hardware component can trigger the invalid format message
  4. An outdated TV firmware can cause a lot of malfunctions on your LG TV, including the “invalid format” error message.

LG TV Invalid Format: Fixes

Here are some methods to help you solve the LG TV “invalid format” issue;

Method 1: Inspect HDMI Cables

Most frequently, the LG TV “invalid format” error message comes up due to loosely connected or damaged HDMI cables. 

There have been numerous occasions where I had to unplug and plug my HDMI cable again to clear this error message. 

Ensure the HDMI cable is connected correctly to your LG TV and the external device.

Check for physical damages on the cable and replace the damaged cables. 

Also, inspect the HDMI port and blow off dust or debris.

Method 2: Confirm HDMI Format

After inspecting the HDMI ports and cables, and everything is still in good condition, check the HDMI format.

The HDMI must be in the correct format for certain features of your LG TV to function effectively.

If your LG TV is connected to a USB drive, ensure it is in FAT32 or NTFS format.

Method 3: Change LG TV Resolution

If the resolution of your TV is incompatible with that of the external device, the “invalid format” message will pop up on your LG TV.

You should consider changing the resolution on your LG TV.

To fix this, try adjusting your resolution with the steps below;

  1. Tap the Home button on your LG TV remote
  2. Select Set up>Display
  3. Navigate the options and select Resolution
  4. Follow other on-screen instructions to modify your LG TV’s resolution based on the resolution of the connected device 

Method 4: Change Resolution on the External Device 

If you’ve changed the resolution on your LG TV and it still displays “invalid format” when you plug in an external device to your TV, change the resolution on that device.

Note: The most compatible resolution for LG TV is the 1080i resolution. So make sure you use this resolution if your external device supports it.

The resolution settings vary based on the external device you are using.

For instance, if you are connecting Xbox to your LG TV, follow the procedures for changing the resolution on Xbox.

You can Google search to find the steps to change the resolution on your device. 

Method 5: Restart LG TV

Restarting your LG TV can clear some minor glitches, including the LG TV invalid format error message, and it’s usually easy to carry out. 

Once I receive this error message, this is usually the first thing I do on my LG TV.

Here’s how to restart LG TV;

  1. Press the Power button of your remote or your TV’s power button to turn it off.
  1. Unplug the TV’s power cord from the power outlet and leave it that way for up to 3 minutes.
  1. Plug the TV power cord back into the power outlet and turn on your LG TV with the power button on the TV.
  1. Turn your TV on to see if the problem persists

Method 6: Update LG TV Firmware

One of the most common reasons you receive the LG TV “invalid format” error message is that your TV’s firmware is outdated.

To fix this, follow the steps below;

  1. Tap on the Settings button on your remote
  1. Go to Support or Customer Support from the Menu
  2. Click on Software Updates > OK.
  3. Highlight Check for Updates and click OK.
  4. Available updates will appear, so select Download and Install
  5. This process will automatically restart your TV. Confirm if you are still getting the “invalid format” error message when it comes on.

Method 7: Clear Cache On LG Smart TV

Clearing the cache on your LG TV can help prevent any software issues that are causing the invalid format error message.

There are currently two ways to clear your cache.

Newer LG TV Models

Method 1: Restart your LG TV

LG now automatically clears your cache when you restart your TV.

You can restart your TV by long pressing the power button on the remote.

Long press the power button on LG TV remote

Method 2: Use the LG Memory Optimizer

You can access a “Memory Optimizer” function on newer LG TVs.

The memory optimizer function will optimize your TV status by deleting unused apps and clearing some of your TV RAM/caches.

You can access the memory optimizer tool by following the instructions below.

  • Settings Button (Remote)
  • OLED Care
  • Device Self Care
  • Memory Optimizer
LG Memory Optimizer tool

This option will also clear non-primary apps that are running in the background.

Older LG TV models

If your TV is an older LG, you must navigate the menu system and manually delete the cache.

1. Navigate to the Settings menu on the LG TV

2. Locate the Storage or Memory option

3. Select the Clear Cache option

Method 8: Reset LG TV

A factory reset is one of the last methods I usually think of.

So, if after trying all the fixes above, you still get the “invalid format” error message, go ahead and reset your LG TV with the steps below;

  1. Tap the Settings button on your TV’s remote
  2. Open All Settings > Support
  3. Select General > Reset to Initial Settings
  4. Choose Confirm, then input your password to reset your LG TV.

Method 9: Contact LG TV Support

Specific hardware components can be why your LG TV displays the “invalid format” message.

Hardware issues are not easy to fix and usually require expertise. 

So, after trying all the fixes above without any changes, I suspect it’s a hardware issue, and you should contact LG Customer Support.


Have you been struggling to clear the LG TV invalid format error?

This error isn’t related to your LG TV but to the external device connected to your LG TV.

With this guide, you can resolve the issue and return to playing games or streaming your favorite movies on your LG TV.