Just to comment forward, this is not a URL that the stock UBB.threads product would produce:
http://www.outdoorking.com/forum/uploads/usergals/2013/01/full-4181-9587-utekeep.jpg

If you're utilizing SirDude's old PicUpload modification, we do not provide support for it; we only support the stock product on these forums.

But, in either case, It sounds like you'd need to convert your old web links in your database from http:// to https://

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