I'm running Windows 7 Professional 64-bit as my development system. After a vinila install, Apache and PHP started, but the Admin and other windows had a buncha PHP errors of file not found. They all pointed to the "Program Files (x86)" EasyPHP folders.
I then removed EasyPHP and installed on my Vista test system. Worked fine. I did have to authorize the EasyPHP program in MacAfee, but other than that, out of the box worked.
After realizing that Windows 7 security has changed to disallow user level access to the various files and services under normal execution, I did the following.
Using Windows Explorer I defined a new folder "C:\EasyPHP".
Ran EasyPHP install and changed the install folder from the default to "C:\EasyPHP".
Installed informed me that the folder existed already and did I want to use it.
I replied "Yes".
EasyPHP installed and started.
Double clicked the Tray icon and verified that Apache and MySQL started.
Right clicked the Tray icon and selected Administration.
It worked and I changed the timezone to Chicago for CST. It worked.
Now I'm in the process of reading PHP, MySQL & JavaScript...