Mamp to Mamp Pro update issue : Yosemite 10.10.2

I updated Mamp to Mamp Pro in order to test Postfix mail on my local machine.
My Macbook is using Yosemite 10.10.2.

After starting Mamp Pro I can not access my fine working website on my local machine.
If I go back to Mamp everything works fine.
Before I start Mamp Pro, I Quit Mamp.
I also adapted the _envvars file name.
MySQL database is copied into the /Library/Application Support/Appsolute/MAMP PRO/db/mysql.
I've been searching for 2 weeks now on many Drupal and Mamp support sites, but can not find the solution.

Can someone help ?
Many thanks in advance
RoWilde