Folder icons I customize keep reverting back to default

[cemster]

Like it says on the title. The only thing I can add to that, this is happening on internal HDD that is other than my OS drive.

I customized icons but after reboot, they keep reverting back to default in Windows 10.

For years this was not an issue and all of a sudden it is...

[vasudev]

Can you please tell how you are customizing folder? Are you choosing icons from icon files like .ICO, .DLL,.ICL etc...? Also have you checked Folder options where the required options are selected or not?