Cannot login to my Plesk

[GlennS]

I keep getting the login screen.

I've tried:

Restarting the sw-cp-server service.
Uninstalling psa-api-rpc (I can't find the source to reinstall it)

 

[IgorG]

What sort of errors you have in /var/log/sw-cp-server/error_log file?

 

[GlennS]

all children busy, launch additional (total 3, limit 30)