Problems downloading xlsx files from our Virtual Desktop client to the local computers

We use an Virtual Desktop environment in combination with our own software and Office. When we open Excel and try to safe files from the VM to the local pc (with de virtual desktop file transfer function that uses the SMB port) we get an error and the downloaded xlsx files can't be opened on the local pc. This problems also occurs with other Excel file types like xls and also with alternative office software (OnlyOffice, LibreOffice, Free Office, Open office.
It seems like every file type can be transfered without problems or errors. Other Office applications work fine. It really is an Excel problem and i can't find a solution. I think it has something to do with the back-up file that excel creates when you save a file.