Keep getting an error when attempting to delete PMs

[dans79]

In my inbox if I check a PM and then scroll to the bottom of the page and select "Delete marked", I get this error when I click Go.

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[hollus]

Did you check if the messages did get deleted despite the error? I assume not...

[Wouter]

Did you check if the messages did get deleted despite the error? I assume not...

I have this problem for more than half a year now. I can't delete any posts, only from the outbox.

[zibby43]

I can’t delete PMs either. No matter whether I choose a single message or multiple.

I get the same error message. I noticed this loss of functionality occurred at about the same time I stopped receiving rep. notifications. Also have to reload the page to submit an upvote as well.