This forum is being overrun with spammers and I have to manually delete many accounts daily. This week I made an error and deleted several valid accounts in stead of spammer accounts, together with their posts.
Normally I have a backup which I can put back, but of course it was Murphey's law: I created a backup this week just before I upgraded the forum software to a new version, in case something went wrong. And I made the mistake with the accounts the very same day after upgrading. Meaning I only have a backup of the old forum version, which I cannot import into the new version!
I have asked for support from the forum creators to see if there's anything I can do to retrieve the accounts or post, but I don't have much hope. The best thing you can do is create a new account.
I'm very sorry for this.
