I have a little bit of cancer on my roof, just above my windshield and looks to go a bit under the seal, and was wondering how many other people have had this problem, what it took to fix it, etc. It's not going through yet. If anyone has an idea of what a new seal for around the windshield would be, it'd be appreciated as well.

 

I had the same problem, rusted under the seal and water started coming in while driving. When a guy came to replace the windshield, he pulled the old one, found the rust problem, sanded it down as best as he could and filled it, looks brand new now.