The could be several different reasons for that. Basically the rule like:
RewriteRule ^7542-this-is-a-link-to.* /7542-this-is-a-link-to-my-website.html [L,R=301]
would fix the problem, matching everything after "-to". But it's not ISAPI_Rewrite that throws 404. It's IIS. I had issues before and all googling ended up with IIS blocking suspicious characters. Try to tweak that.
It could be this "dots in the URL"
This thread has a lot of useful info