[villagetinker]

Originally Posted by keepsake

After ten years I can attest to this fact: Solar panel drippings cause corrosion on otherwise perfect metal roof. I have the Galvalume sheets. Only place with rust is along the drip edge of the aluminum framed panels. If a contractor had told me back at install to paint that drip area, this could all have been avoided.

You have a classic problem of Aluminum in contact with steel, these 2 metals do not play nice together. I doubt that any amount of paint would have stopped the problem. I always try to use stainless steel hardware if it is going to be in contact with aluminum. I would suggest try calling Eastwood (yes automotive products) and see if any of their excellent rust preventative solutions will help with your situation.
Hope this helps.