Resolved: Administrative service for this server is not enabled

Yesterday one of my developer installed a web part using addsolution command of stsadm, After that he navigate to
Central Administration > Operation Management > Solution Management.
He tried to deploy the installed web part in more then one web application immediate and encountered an error that
The timer job for this operation has been created, but it will fail because the administrative service for this server is not enabled. If the timer job is scheduled to run at a later time, you can run the jobs all at once using stsadm.exe -o execadmsvcjobs. To avoid this problem in the future, enable the Windows SharePoint Services administrative service, or run your operation through the STSADM.exe command line utility.
Oops ….
He came to me and told the problem so i am discussing here how i resolved this for him.Now how to resolve this because now u find in solution management there is an error occured in front of installed web part.
So here is the solution for all problems.

Go to Start > Run
Type services.msc
Now in Services window select “Windows sharepoint services administration”
Right click and start
Now the above mentioned error will not occur again

Now you have to retract installed webpart to reinstall it again (If you try to reinstall it directly stsadm wil say that
solution exists already in store). Now how would you retract this error installed web part ?

* As this webpart is deployed in more then one web with error so you have to retract it one by one from all webs ( You can’t retract
it all by once). You have to run stsadm -o retractsolution -name “<your solution name>” -url “the site url in which this web part deployed”
for each site in which error causing web part is deployed.