This is a very common scenario that you need to restore the older version of release and your application is deployed via ClickOnce method. Below are the some links which I found found very useful in order to resolve this issue.
http://geekswithblogs.net/gpro/archive/2008/10/30/clickonce-restore-previous-version.aspx
http://www.codeproject.com/KB/dotnet/Restore_Application.aspx