I found the following question but if possible I don't want to have to make changes that will affect all sites on the server. HttpBrowserCapabilities.Crawler property .NET
I also found instructions on using the browserCaps Element http://msdn.microsoft.com/en-us/library/sk9az15a.aspx but it seems to be deprecated.
What is the easiest way to detect the major search engines in Asp.net 4.0?
(I am only really interested in being able to detect major search engines)