Cannot login Gallery 1.5.7

I was having trouble with Gallery 1.3.3 so I upgraded it to 1.5.7 The front end is working fine however when I try to log in as admin I get invalid password so I try to go to the setup wizard and get a 500 error. I removed the .htaccess file as instructed by the FAQ however now I get the following error

Fatal error: Cannot redeclare getrequestvar() (previously declared in D:\Webspace\rumrunnersfun.com\wwwroot\gallery\util.php:39) in D:\Webspace\rumrunnersfun.com\wwwroot\gallery\util.php on line 39

Any help is appreciated.

BTW the site is hosted on a server that I only have FTP access to.

Also it is a Windows server using IIS.