Unable to login to the Admin Client

Hi Experts,

Need your help on below mention issue.

My client was using BPC MS 10.0 SP5 and I upgrade it to SP13, everything was installed correctly without any error. After installation I restore their production environment (which was built in SP5) into the upgraded server (Sp13). While testing it I figured that I am not able to login into the Admin Client though I can login into the Excel and run the reports without any issue.

The admin client is also updated with latest version. (10.0.13.0)

Any idea ?

Thanks,

Charly