I am having this very same problem.
I tried everything.
Just even download the whole core/db again and did a clean install.
Is any update with world db has to do with that error?
The only comands I can use right now are .gm on/off, mod speed and levelup. Besides that I cant use anything.
Can anyone PLEASE do a step by step to add an account to have all commands or any command?
Really appreciate. Trying this since yesterday, I read everything and did many searchs, but I cant figure this out
EDIT: Whoever is getting that same error, mine was solved after I updated my command table. Freaking thing