To help you get started:
You should check the client log.
Open Administration tool, you don't have to log in.
Double click the "Log file" menu option under "Local Settings".
Anything more useful there?
Is the correct SQL user and password specified in the DB and Archive server settings?
Is it only one client, or a general error?
Can you log on from the server?
It is general error on both client and server.
I was not able to log in from server machine also.
I am able to log in to SQL with sa username. And also I checked the Archive server settings there is no issue with Administrator.
Also will you please help me for which error I should be looking for in client log?
Not sure what to suggest you but have you contacted your VAR?
I've seen this before, I cleared it by deleting the files in %AppData%\Roaming\Microsoft\Crypto and restarting. That might be huge overkill though and cause other issues so it's better to use procmon: Process Monitor to find the exact file in there it's accessing and delete just that one.
This was actually a HUGE help. I was able to create a filter within ProcMon.exe for Path contains Crypto\RSA and then attempt to log into EPDM. This identified the exact key that it was accessing. Deleted that single key and the user could log in again.
I just reinstall the Solidnetwork License Manager Server and it's working fine.
But it might not be the proper solution.
I solved this problem by log in to Windows with another Windows user,