I recently upgraded to the donor client, but then I started experiencing a glitch where minecraft would just close automatically as soon as I logged into any server or singleplayer world. I forced update but the glitch still happens. It also creates an icon on my desktop called 'hs_err_pid_(Number)" whenever it closes. Does anyone know how to fix this?

force updating only wipes the .jar. try deleting the whole .minecraft file under %appdata%/roaming. be sure to back up your screenshots and world saves if you dont want to lose them.

Alright. ^^