I have a client where it appears every few days their server creates an exact copy of it's drive on the office computers. So, for example, the server's drive everybody uses is S: then after a few days the server will make a copy of it and the users will see an S: and an F:. Both are exact copies of each other. Both drives have all the files and the files have no issues opening. When saving in the usual S: the file instantly is also copied to the F:. Deleting the F: has no impact on the S: and the main drive continues to operate as normal until a few days later then we'll see a G: that is a copy of the S: again.