I rebooted my HTC Jetstream because – like marriage – it seems a good idea at the time. I then entered the dreaded HTC Jetstream reboot loop. The device boots to the lock screen. Slide to unlock. Reboots. Consulting Mr. Google, I learned I was not alone. The problem may have to do with the SIM card; one suggestion was to remove it. There were other suggestions, some not printable.
Anyway, I was rebooting in landscape mode. Something possessed me to rotate the device to portrait mode. Amazingly, that worked. Later, I saw some posts from others this worked for also. Not sure why this worked, but it beats a reboot loop.