RPI3 - Server refused to allocate pty

[bassie127]

I am running arch linux om my RPI3 for years.
It is a headless system, so I use alwasy Putty (on windows) to ssh into the RPI3.
System is completely uptodate.

SInce last week I get the login prompt, and can login, by I can't do anything, because of this message: Server refused to allocate pty

Rebooting doesn't fix this problem.
Any suggestions?