Hello amishra123,
it is not compatable with windows 7 as yet and I dont know if Microsoft have any plans to make it availiable to Win7 as it is being retired next year once all the current subscriptions run out.

You can however download the AntiVirus software engine that Live One Care uses as a stand alone application. It is availiable for free from Microsoft and is being distributed as Microsoft Security Essentials. You can get it from here

http://www.microsoft.com/Security_Essentials/

I have been using this since its release and have had no problems so far. It has also recieved numerous reviews and they seem to be favorable.
As with any antivirus software you must still use common sense.

If you want the other functions that Windows Live One Care has you can look up the help function and you can find out how to setup automatic backups and clean out your system using schedualed tasks.

The work around is uninstall Windows Live One Care. Goto http://www.microsoft.com/Security_Essentials/ and install the new antivirus solution from Microsoft.

Its not a work around its a new program and its free to use with genuine Windows software