TeamViewer drops connection when getting to this stage

Hello, when attempting to connect to a machine using unattended access, I get to the above connection stage and the connection just drops. TeamViewer does not crash completely but I just get returned to the Computers and Contacts screen. This error does not occur to every machine (in fact most of my connections work OK), it just seems to affect a couple of them. I have made sure that TeamViewer is updated to the latest version but this doesn't help. I have also made sure that remote connections are allowed to the affected machines in the advanced system settings of Windows 10 (this fault is not exclusive to Windows 10 though).

I have been having these issues for a while and have worked around them using other RDP solutions but I can't find anything about this issue when searching on Google.

Any help would be appreciated.