I'm wondering if there is a way to set the overall default font in SD+, for all email correspondence?

I have tried the suggestions in the following thread;

https://forums.manageengine.com/topic/change-default-mail-font#49000007809269

I have tried changing the font in all the reply/forward notification templates we use under    Admin-->Notification rules--

However when I press save and test the email, the font is reverting to Arial or Times New roman. 

We would like to set it to Veranda for all email correspondence if possible. 

We are using Build 9035 with an MSSQL database. 

Many thanks