Driss73
You wrote
-I am not using an account with administrator privileges
That very well may be the answer. Make sure that you are running the program from a User Account with Administrative Privileges. In addition, right click the program's desktop icon and apply Run As Administrator. Both Premiere Elements and QuickTime require Administrative Privileges.
Also for consideration...
Let us start by going through the usual Premiere Elements 8 drill...
a. Are you working from the 8.0.1 Update of the program? From what you wrote, the answer appears to be yes.
b. Is the automatic Background Rendering and AutoAnalzyer features turned Off?
For Background Rendering, see Premiere Elements workspace, Edit Menu/Preferences/General and make sure no check mark next to the Background Rendering option..
For AutoAnalyzer, see Elements Organizer workspace, Edit Menu/Preferences/AutoAnalyzer Options and make sure they are all turned Off.
c. Have you deleted the Adobe Premiere Elements Prefs file and, if necessary, the whole 8.0 Folder in which it exists.
Local Disk C
Users
Owner
AppData
Roaming
Adobe
Premiere Elements
8.0
and in the 8.0 Folder is the Adobe Premiere Elements Prefs file that you delete. If that does not work, then delete the whole 8.0 Folder in which the Adobe Premiere Elements Prefs file exists. Be sure to be working with Folder Option Show Hidden Files, Folders, and Drives active so that you can see the complete path cited.
There is an Adobe document on troubleshooting damaged products, but I am not sure how useful it would be if you cannot open new project.
http://helpx.adobe.com/premiere-elements/kb/troubleshoot-damaged-projects-premiere-element s.html
But, you may want to review its contents.
Have you looked at the issue with and without the antivirus and firewall(s) disabled?
We will be watching for your progress.
Thank you.
ATR