"Two separate devices" sounds like this is the sort of situation others have been describing.
If, however, a drive starts out looking normal, and spontaneously repartitions itself into two partitions on one device, that's usually a sign that the drive has a bad section of flash RAM. The only thing to do at that point is copy over all the surviving data, contact the manufacturer for RMA exchange if it's worth it, and trash it if it isn't. There will be a chunk on the drive that can't be written to, that most disk utilities won't detect or mark bad if you repartition, and that may get worse with time.
Seen that twice; once on a drive of mine from ACP-EP — they were prompt in the replacement. Once was on an unhappy student's Cruzer drive; I don't know how that ended up. |
