Loose Exterior Seal - Leak at Storage Box

[Dimegroup]

At the front of my storage area on my pop-up, a weatherstrip covering has worked it's way loose. This is the covering that seals the corner of the storage unit formed by the front and side. I'm looking for ideas for what it takes to clean up this area and re-attach this covering, including water-proofing. Thanks.

[BigBaron]

Can you post some pics of the area(s)? It's a little hard to know exactly what you'll need without them.