Group Policy import error - no backups found

This annoyed me for about an hour today! I had copied some group policy backups to a new domain but when I tried to import into a new blank GPO I got an error saying no backups found. I discovered that the manifest.xml in the import location had all the gpo data removed. Checking the original backup location in the original domain I could see it contained data for each group policy backed up. Digging a little further I realised I had an apostrophe in the name of one of the group policies I had backed up.  So I removed the apostrophe and backed up again, then copied over to the new domain. Success! I guess the xml didn't cope too well with the '. So lesson learnt to be careful with non alphanumeric characters in group policy names.