Ok Thanks Dan.
That error means, that the downloaded file. The one you specified in your xml is not available anymore.
Most likely that the AV software removed it.When you deploy ubot bots with it, they are very often classified as a virus, because of the encryption.
And some AV software remove those files.
So check the log of their AV software and see if it deleted that update file.
Besides that.. check what the difference is on their systems? Non windows 10 IS? Different language?