Remove old windows install caused reboot to fail

[stanhol]

After using the Advanced - clean 'Old Windows Install' option, my Surface Pro 4 will not boot. Apparently some file required for the boot process was in the 'Old Windows' folder. Using a boot USB stick and running the Windows repair doesn't correct the issue. Had to 'Reset my PC' to get it running. That also requires reinstalling MS Office and numerous other apps. Did not lose any data but it was a pain and I won't do that again.

[nukecad]

I actualy did this last weekend for a friends HP notebook with no problems at all.

 

Ran CCleaner to remove temporary files.

Ran various malware/adware scans and removed PUPs and PUMs, defragged etc.

Updated it from Win10 1511 to Win10 1607. (AVG Free had been blocking Windows Updates for over a year, uninstalled AVG before updating).

Rebooted and used CCleaner to remove the 'old windows' files.

 

Laptop is now booting and running much faster than before.

 

There should not be anything in the 'Windows.old' folder that is required by the current operating system.

It's just a backup of the old version of windows that you have replaced.

Windows will automatically delete this folder itself after a month.

 

Did you maybe also run the Registry Cleaner in CC?

This is much more likely to have 'broken' something if you removed a needed registry entry by mistake.

That could also explain why the USB boot would not work.

[stanhol]

Re: There should not be anything in the 'Windows.old' folder that is required by the current operating system.
It's just a backup of the old version of windows that you have replaced.
Windows will automatically delete this folder itself after a month.

 

That WAS my understanding as well. 'Old Windows install' was more than 30 days old which is why I used that option. Did not try the Windows 'Disk Cleanup' option, Did not run 'Registry Cleaner' in CC.