avast ms outlook exchange

Hello ,
Before , when i clicked on a contact link , normally openned my outlook express , but now it opens the office outlook with a message of avast ms/outlook exchange …how do I put it back as it was ???

thanks

This is not a avast problem i think, the problem is probably that you have changed what mail progam that is default

I guess it is XP you have?

Start> Control Panel> Add Remove Programs> Set Program Access and Defaults> open the folder that have a tic
and here you sett the mail program that you want as default

Here is a different way
http://www.freeemailtutorials.com/outlookExpress/outlookExpressTipsAndTricks/setOutlookExpressAsDefaultEmailClient.cwd

did it work?