Program works for one user but not another

I am using MS Vista Home Premium and have been successfully using an older
version of Photoshop. Now when I try to load it, it says "Program Not
Responding...". I decided to uninstall the program and reinstall it, but I
was not permitted to reinstall. Screen asked for permission to run program
and then would just stop trying to install. I created a second user account
which allowed me to install and use the software fine, but when I use the
original (administrator) account, it does not load and just keep "Not
Responding..."

Totally lost,