I have a user, one of many in our Office 365 exchange system. When their OST data file reaches 15 GB. It displays as disconnected in Outlook 2013. I redone another profile, works great but when it reaches 15 GB does the same thing. I have tried compacting the data file and reducing the cache time down to 3 months but remains disconnected. Nothing short of redoing the profile again with the 3 months cache time. I am not sure what to do. Any ideas?