When an AV found a virus on my external drive in the System Volume Information folder, I could not understand why this folder appeared there in the first place. From the logic behind System Restore there should be no cases when the system creates restore points on the removable media (except maybe manual installation of a program file there). Or I miss something and there are chances this folder would appear on any removable media one day?
System Restore may also monitor the external drive. This is of course a bad idea.
A possible workaround is to assign a permanent drive letter (the higher in the alphabet the better) to the external drive via Disk Management. To access Disk Management, go to Start - Run and type diskmgmt.msc then press enter.
Right click a partition, logical drive, or volume, and then click Change Drive Letter and Paths.
Do one of the following:
Now go to System properties and do:
To get rid of this protected directory from an external drive, say G:, start cmd.exe using "Run as administrator" and enter the following:
Answer y for yes when asked whether to replace the permissions.
After this you can now delete the directory.