I tried two Outlook email addins I did not like: Ella and Kubi

Each made my Outlook mailbox behave weirdly.  Ella, was better for screening spam, but I deleted it, finding Cloudmark a much better, more accurate tool.  I was more hopeful about Kubi from Kubi Software for collaborative email.  I couldn't make this tool work at all, even though I fiddled with it for several hours.  C'est la vie.