ERROR: Regular Labs Library Plug-in Is Not...

I just did an update to wattampainenglish.com using the Joomla update function. ALL of my installed updates shows "Regular Labs Library Plugin is not installed."

UPDATE: Reinstalled Extension Manager and the error was resolved. I was able to update. I just updated my other two websites without any errors.

Thank you for your quick response.

The error messages all start with "Regular Labs Library Plugin is not installed". I just reinstalled the Extension Manager and the problem seems to be resolved altho I want to do some more testing. I was REALLY surprised with this error. I've used your extensions for about 10 years and this is the first error that I have received. Thank you for the quick support. Tom