STSADM -o authentication -url
Now, when we access the site it was giving AccessDenied error.
After our analysis, we figured out that the Database was not correctly updated with the job.
So we did 2 steps:
#1: From CA, we changed the authentication mode to Windows - Successful. We changed again to Forms - Failed.
#2: Now we are our fav command : ststadm -o execadmsvcjobs
Success. Now the mode is correctly changed as the job status is complete.