virtualbox.org

i can confirm this problem happens too when copying file from shared folder to the guest operating system (host: win 7 pro sp1 64bit, guest: ubuntu 11.10 32bit).

older virtualbox 4.1 and lower didn't have the problem, only current and not so latest version has this problem.

"Error splicing file: Protocol error" was the message.

I can also confirm this problem happens from host win 7 pro sp1 64bit to guest linux mint 11 32bit
I'm also using VBox 4.1.2, so an older version - I automount my shared folders.

Note:
This didn't happen a few days ago, so I'm not sure what I've changed on which OS to cause this.

WORKAROUND:
I did find a work around if you're stuck... Compress the file(s) you want and open the compressed
file in your guest OS using an archive manager, extract to guest OS. Files copied! Perhaps this
points to Nautilus being the problem?

It also happens with pcmanfm and thunar so it's not just a nautilus issue.

Windows 7 64bit Host
Ubuntu 11.10 64bit Guest
Copy work fine.

Windows 7 64bit Host
Ubuntu 11.10 32bit Guest
Not work!

I'm afraid "work" and "not work" are not particularly useful descriptions.

In my case filenames were not supported by Windows machine.
After I changed the filename copying was successful.
For instance
needed to copy Screenshot from 2019-10-22 10:56:47.png
I had Protocol error.
Changed to Screenshot1.png
Copying was successful.

Yes, it could be that. Colon (':') is not allowed in Windows filenames, so any attempt to create such a file in Windows will fail.