Xampp Installation Problem on Vista

[smokinguns]

I installed xampp on a machine with vista business SP1 version. The default page(with the "You have successfully installed XAMPP on this system" msg) opens up fine.PHP activated when I click status on this page.
But when I put a php page in the htdocs folder and try to access it using 127.0.0.1/mypage.php, I get the "Object not found" error.. The apache service is running as indicated by xampp control panel. I clicked the "Port-Check" button on the xampp control panel and this what it says:

Service Port Status
Apache(HTTP) 80 System

I checked with a XP machine and it says
Apache(HTTP) 80 C:\xampp\apache\bin\httpd.exe

How do I resolve this issue? I have disabled windows firewall and UAC

[Wiedmann]

But when I put a php page in the htdocs folder and try to access it using 127.0.0.1/mypage.php, I get the "Object not found" error..

So there is no file "mypage.php" in the htdocs folder.

In the error.log you can see which path/file Apache exactly tries to load.