After recovering a partition, I can see the files and folders in Partition Recovery but Windows is still not able to see the contents or reports an error message. What could be the problem?
When the operating system thinks it needs to format a drive there are 2 main things that may have gone wrong:
One is that the partition information itself, which is the information that tells the operating system how the disk is partitioned, where the partitions start and stop, and where the start of the Master File Table (MFT) is and so on can be corrupted or lost. Partition recovery can figure this information out and re-write it. If just the partition information was damaged, the files will become visible to the operating system once the partition information is corrected.
The other is that the MFT (or fat records for a fat file system) can be corrupted. Partition Recovery can not repair that. It reads the information in it differently than the operating system does and ignores some parts of the information it does not care about. There may be errors in the MFT that stop the operating system from seeing the MFT or fat records properly, but we ignore these errors and can show files the operating system can not. Partition Recovery can not fix these errors (it might not even know they exist) so if that part of the drive is damaged, Partition Recovery can not help. File Recovery reads the MFT and fat records the same way partition recovery does, and ignores the same errors. It also can not fix the errors, but it can copy the files to another drive. Partition Recovery fixing partition information would definitely make it easier for File Recovery to do its job.