the DU server may suspect there's something wrong with your connection...

usually figures out you're ok within a day or so...

That could be it, or there's a weird bug that EarlG knows about, where special characters or combinations of them upset the routers and filters meant to stop evil-doers.

And in the past, removing them cleared up the problem, but it was trial and error.

If it persists, post in DU Community Help forum, where it's more visible than this crowded forum.

Good luck.

I had the same problem a while back and it turned out to be a misaligned Finnegan Pin.