daveite:
Do you by any chance have this add-on installed:
https://vborg.vbsupport.ru/showthread.php?t=150761
If so, disable it and see if you still get the error. That worked with me with the new updated code for the plug-ins now posted above.
If you don't have that specific add-on installed, please look for any other products or plugins that modify the postbit and report them here.