Last night my HTC Thunderbolt displayed a blank black screen and I couldn't get it back to the desktop. I had to remove the battery to shut it down. I turned it back on and it took longer than normal for it to boot up. Now i when i turn on my hotspot it show that it is on but I do not see the normal icon and when connecting my device it show connect but no internet. Now I also can not power off my phone when holding the power button. I do not get the regular menu that provide me with the choice to power off.
No Hotspot is no fun! I love sharing my internet connection via Hotspot and I can certainly understand how frustrating this issue must be for you. The fact that you are not able to power off your device points to these issues to be associated with 3rd party applications conflicts. I have also seen this behavior when devices sustain water or physical damage.
To check for 3rd party applications conflicts please run your phone in Safe Mode http://bit.ly/vifLpt and test. If issues stop, you will need to identify the bad application (s) and delete from your device for good. If issue continues while on Safe Mode, do a factory reset http://bit.ly/NdQpOF and test. This procedure should also resolve the inability to power off the phone.
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