Robocopy Mirror-copy silently failing

Hi!

I’m using Robocopy to make a copy of an entire directory and it completes successfully without any warnings - except 12 failed files which is certainly tolerable.

However in reality only 23k of 93k files or 35GB of 75GB is copied. The rest isn’t.
What the actual f*?

I’m logged on as domain admin, running powershell as admin and executing the command from there.
The source is a UNC path mounted locally as R:\ using the same domain admin credentials. The destination is a local disk.

Please see the image for details.

Any suggestions/info greatly appreciated. This doesn’t make any bit of sense to me.

Thanks!

I’ve had problems like this with robocopy in the past. I don’t really trust it at all, and would rather use xcopy instead (if you don’t need to copy the ACLs).

I can’t recall if my robocopy issue was resolved by not using mirror mode. I made some notes from our last (working) migration where I used the following flags:

robocopy x:\zzz c:\zzz /e /copyall /v /zb /log+:robocopy_zzz.log /tee

At least with a verbose log you should stand a chance of spotting skipped files.

1 Like

Alright, solved the problem.

Turns out it isn’t a problem with Robocopy but a a bug in Windows 10.

Robocopy successfully copy all the files (except the ones it correctly lists as failed).
But when I right click the folder I copied the data to and select Properties to check the size and file count it doesn’t show the right numbers.
It seems to only include subfolders at the first level or something similar (haven’t bothered figuring that out).

WTF?
I’m 99,9% confident that since Windows 95 that number should reflect the size of the entire folder with all subfolders, no matter how many levels deep.
Microsoft, please fix!