Easy way to check what files are missing

Question

I have 2 hard drives, I copied everything from one hard drive to a fresh drive, but some files didn't copy as they were corrupted. Is there an easy way to check what files from one hard drive are not on another?

Answer 1

robocopy sourcedriveletter: destinationdriveletter: /MIR /LOG:logfilename.txt /TEE /L

Robocopy is a command-line tool built into windows. You can check the options by opening a cmd prompt (for this purpose, probably as admin I suppose) and typing robocopy /? or robocopy /? > %USERPROFILE%\desktop\robocopyoptions.txt if you want a text file version of the help doc.

In my sample above, /MIR means "mirror" and it duplicates "source" in "destination," and deletes anything in "destination" that is not in "source."

/log: logs to a file, /TEE outputs to the console as well as the logfile.

The final command /L sets it to list only, and will not actually copy or delete files.

The log will very clearly show you which files in the source do not exist in the destination.

Of course, I strongly urge you to examine the help docs first to ensure my example is correct.

Answer 2

feedback from OP: excel method did not work for him, Matlab method is untested I have a very inelegant solution, but I think it does the job (assuming your have excel). It only works if the number of filenames fit in excel. (excel has a limited Max number of rows: 1,048,576).

Go to cmd (I'm assuming you are on windows). Change directory to the first drive. Type:

dir /s/b/o:gn > drive1.txt

Do the same for the second drive, but change the name of the txt file.

I took the cmd line from: https://stackoverflow.com/questions/3447503/how-to-get-a-list-of-sub-folders-and-their-files-ordered-by-folder-names .

Copy both outputs in excel(assuming 2007 or newer). The easiest option I know of is the following:

• Select the columns that contain the cmd outputs.
• On the data tab in the Sort & Filter group, click Advanced.
• In the Advanced Filter dialog box, do one of the following:
  • To filter the range of cells or table in place, click Filter the list, in-place.
  • To copy the results of the filter to another location, do the following:
    • Click Copy to another location.
    • In the Copy to box, enter a cell reference.
• Alternatively, click Collapse Dialog Button image to temporarily hide the dialog box, select a cell on the worksheet, and then press Expand Dialog Button image.
• Select the Unique records only check box, and click OK.
• The unique values from the selected range are copied to the new location. The original data is not affected.

This way you should have a list of all the unique filenames, which is the Same as a list of all the filenames that weren't copied.

The excel procedure was in the end taken from: https://support.office.com/en-us/article/Filter-for-unique-values-or-remove-duplicate-values-d6549cf0-357a-4acf-9df5-ca507915b704#bmfilter_for_unique_values

Alternatively you could use the cmd command in Matlab.

The command in Matlab could be:

DosCommand=sprintf('%s %s','dir /    B',directory);
    [status, cmdout]=dos(DosCommand);
end
Filenames = strread(cmdout,'%s'); 

Then execute:

NonCopiedFilenames = 

A(sum(bsxfun(@eq, A(:), A(:).'))==1);

The unique values trick was copied from: https://stackoverflow.com/questions/19236914/how-to-find-a-unique-value-in-a-matrix-by-using-matlab