I just installed a fresh copy of the forum at the root directory on a hosted IIS server. The installation completed OK and did not give any errors. When I clicked on "View your new forum" it gives the below error message.
PHP Fatal error: Call to undefined function: allowedto() in C:\Domains\website.com\wwwroot\Sources\Load.php on line 662
I tried to search the forum for this error but the search was turned off because of the heavy load. I hope its has not already been answered.
Try reuploading the Source files with a different FTP client. Try FileZilla (http://filezilla.sf.net).