Each will have to start Checking file system on G:

Checking file system on G:
The type of the file system is FAT32.

One of your disks needs to be checked for consistency.You
may cancel the disk check, but it is strongly recommended
that you continue.
Windows will now check the disk.
Volume Serial Number is 7D64-8A89
The specified disk appears to be a non-Windows XP disk.
Do you want to continue? (Y / N) No

you installed other systems? If not, after the G Copies of important documents out of G and then set format on the line.