I have a Droid2Global, but I imagine the process is the same. Charge your battery to full (I don't know if this is required, but it's recommended on the TBH instructions, so I do it). While it's charging, download and install RSDLite and the latest drivers for your phone (As well as the SBF for your phone). If the phone can be powered up, power it up, plug it into your computer, and put it in PC mode. (I also have USB debugging checked under Settings -> Applications -> Development.. I'm not sure if it's required or not). If it can't be powered up, plug it into your USB port, pull the battery, and hold the up arrow and the power button to get the bootloader. It should say something like "Bootloader number 0.xx Memory OK, Connection: USB OK to flash" or something like that. Start RSDLite. Click the "...": button next to the window on the left side. Select your SBF file. In the bottom section, RSDLite should recognize your phone (A955?) as being plugged in. Select the phone, and and hit start. RSDLite takes over from there. At the end, it will reboot your phone. RSDLite may display a message saying "Please manually power up this phone" even though it's already rebooted. Don't panic. Go to the task bar and switch the USB connection back to PC mode. This should make RSDLite switch to "Pass". Wait till you get the pass message to be sure your phone is back to its full functionality. Whenever I do it, I boot into recovery and wipe my cache/date partitions, just to ensure a factory fresh start, to make sure I erase whatever bugs were plaguing me. Once you SBF and have it back to where you want it, make sure to do a nandroid backup, so that next time you can save yourself some hassle.
