when i sign on my mac pro shuts down
when i sign in with password; computer shuts down
Question marked as
What year model and what macOS...?
see > Identify your Mac Pro - Apple Support
See if it will startup in Safe Mode, as per > Use safe mode on your Mac - Apple Support
If not? Try Disk Repair in Recovery, as per > Repair a storage device in Disk Utility on Mac - Apple Support