type *#*#3424#*#* and you will enter in HTC Diagnostic menu 3424 means (DIAG)
type *#*#4636#*#* and you will enter in HTC Info menu 4636 means (INFO)
type *#*#8255#*#* for launching GTalk Service Monitor 8255 means (TALK)
To boot your device in SAFE MODE, remove your battery, start your phone and press Volume Down key when HTC logo appear. Keep Vol Down key pressed until your OS is loaded complete. You will notice SAFE MODE in the left lower corner.
In this mode, none of your 3rd party application will be loaded
