OK, I typically upload my pics to my account on PhotoBucket and then copy the URL link from there to use here in this forum.
I think as a new member you are considered on probation for 100 posts or so, maybe even a time period too. Then you can upload up to 100 photos into the photo gallery. I think they restrict it like that to block the spammers and the trolls that are constantly trying to screw up things.
I had that same problem a long time ago, when I first signed up too.

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