It will be a bit complicated. I hope I can explain it.
I tried to read the forum previously and I have found many problems with the Admin Panel link showing only a white page, but nothing seems to match my problem, so I try:
I installed 4images. Everything was fine. I made pretty much modifications, like new internal pages, templates etc. Everything worked fine. Then I realized that I have to move to a new subdomain on the same server (it's a free webspace provider). I exported the database, I created the new webspace, I imported the database and then I uploaded all files to the new FTP (without install). As I said, everything on the same server, just another subdomain.
Now everything works fine, but if I click the admin panel link in the footer, I get a white page. Now it comes the difference: if I delete "index.php" in the URL field of the browser, so i have only
http://mysite.com/admin and I hit enter, the admin panel loads fine.
I tried to modify the link in the page_header.php and delete "index.php" from it, but then I can't load admin ever.
The modifications are not the problem. They aren't too deep to cause a problem, but enough for fresh install not being an option.
Anybody an idea?