The following is a list of error messages that may be displayed.

Disk parameters look dubious, run in manual mode

The wizard has done an analysis of a FAT disk and can not determine good values for cluster size, and cluster 2 start.  It is advised to run in manual mode and determine working values.

No MFTs seen

There have been no MFTs detected fro the partition.  This is probably because the $MFT file has been corrupted.  The solution is to use the option to scan the drive for MTFs entries

Only unalloacted data may be recovered from unknown media

The type of media has not been determined  ie it does not now if it a FAT, NTFS etc disk and so only an Image Raw function can be used.

Very few files found, try an image scan?

The wizard has not found many files.  Try an Image Raw scan to see if there are more files