ROCK Power failure - external hard drive

[Suedkiez (Just a fellow user like you)]

If the drive is NTFS as @BlackJack suspected, here is a bit more info and detailed solution:

Nucleus will not recognize USB external hard drive

Formatted for Windows means NTFS, Microsoft’s file system for Windows, if you didn’t reformat it with a different file system. Your issue sounds like it might be caused by the better/safer but therefore stricter NTFS support that was added in RoonOS build 254 in November. There were quite many of these issues because it was discovered that quite many people had been using NTFS external disks that were not in the best state, which had previously gone unnoticed. The disk may have been previousl…