What does it mean to have a red exclamation mark on HTC mobile phone?

If a red exclamation mark appears when updating the system, the update is wrong and needs to be stopped immediately. If you send a message and make a phone call, a red exclamation mark usually appears because the signal is too weak to send a message, or you sent a voice message. If the recording time is too long, it is easy to be prompted that the message transmission failed, and short messages will occasionally appear, but the frequency is not high. Just send it again.

Solution 1, enter the system, back up the data, restore the factory settings, and try to download the update again.

2. If you can't enter the system, you can try to restore the factory settings by key combination, press and hold the volume down key+power switch, and then enter the engineering mode. Then download the update again. "FACTORYRESET" in engineering mode will cause the phone to lose all data, including the built-in storage space.

3. If the above operation fails to restore the normal use of the mobile phone, it is recommended to bring the invoice card and send the mobile phone to the HTC maintenance center. (Note: Data in the mobile phone may be lost during maintenance)