After you finish installing the ServiceDesk application, you should immediately complete the postinstallation configuration wizard.  If you wait too long, the process times out and you have to manually relaunch the postinstallation configuration wizard by opening up a Web browser window and browsing to:

http://localhsot/SD.Installation.PostInstallWizard.default.aspx

If you are unable to relaunch the postinstallation configuration wizard using this method, you must rerun the ServiceDesk application installation from the beginning. The wizard is only available for completion on time (it is deleted upon its first completion).