Can't share a lot to the Exchange, "Failed to Save" message

I've tried about a hundred times to share a lot to the Exchange. I just want to put all my custom content in one house, share it, and delete all the other lots I've got to save some room on my hard drive. I looked up my problem several times on different sites and with different phrases, and I've done everything I've found to do to try to fix it. I made the house smaller, cleared my uploads, set my graphic settings as low as possible, bulldozed the lot before saving it, renamed the lot, and I even tried to share a house without any custom content in it, it still fails no matter what.

Can someone PLEASE help me? This is beginning to seem impossible.