I use Office for Mac 2011 linked to 365 and synced to an iMac and MacBook Air.  

I use this daily and often and have many contacts all assigned across something like 15 different categories - all colour coded.  

My contacts file is not affected by this issue.  

But my inbox used to pick up the categories.  However, in the last 3-4 weeks, the inbox now randomly drops the category and colour code.  

Currently I have two emails from one person - one is coded/categorised, the other is just black text.  

Often when I open up the inbox at start up, I can see the items all coloured and then watch as most of them de-categorise.  

Any help would be much appreciated.

I am no techie but would probably call myself a gifted amateur - usually can get my way around but do not understand highly technical stuff.  

Thank you