Hopefully you have access to your database.
If not, perhaps the techniques used in this solution will work:
http://blogs.snapsis.com/PermaLink,...1906.aspx.You will want to change the Friendly URL Settings to false, so you will need to change one line in the file, the one that defines the string that contains the SQL to:
string sql = "Update {databaseOwner}{objectQualifier}HostSettings Set SettingValue=F Where SettingName="UseFriendlyUrls";
I think that is all that is needed.
You will need to FTP or otherwise move the file into the installation's root directory. Don't forget to remove it when you are done, as it leaves a bit of a security hole when it is there.