I found this thread because we had a similar problem, and just thought I would add a note for future “searchers”.
We had a problem like the one mentioned, and in our case, the clients having problems were using Lotus Notes mail client.
In our specific case, the codes were inserted by aspose when converting empty lines (containing only a paragraph symbol in word).
After numerous attempts, I found out that any attempt to replace the code with either a normal space " " or nothing “”, resulted in formatting problems in other mail clients (tested: outlook 2003 & 2007 and Gmail), as these would then simple delete the empty lines.
The final solution was to replace with the html-entity version
This fixed the problem in Lotus Notes without messing up the formatting in the other clients.
I wonder if there is a specific reason (maybe opposite issues with other clients?) for Aspose to use the xml version of the entitiy instead of in the first place?