There are 2 typical ways to do this -have multiple websites in IIS (either using domain names you have or using host file entries to allow for unique names http://support.microsoft.com/kb/228760 ), or by adding applications under the same IIS site e.g. localhost/dnn1 and localhost/dnn2 . If you do the second approach you have to be aware that as dotnetnuke cookies are set to domain level (/) expiring a cookie in localhost/dnn1 would expire it in localhost/dnn2. However if you're not logging in what you're seeing is collisions with same named auth cookies. If you look into your web.config you'll see a line such as

<forms name=".DOTNETNUKE" protection="All" timeout="60" cookieless="UseCookies"/>

Notice that the forms auth cookie has the name .DOTNETNUKE - as these cookies are further protected by machinekeys unique this will cause your logoff issue i.e browsing from 1 site to another under the same domain with the same auth cookie but different machinekeys causing the cookie to attempt to be read by a different machinekey and fail. The easiest way to work around this is to give a unique name for each application under the same IIS website.

Hi Mr Connolly,

On the same topic! I really need your advice on a current Ontario government DNN 4.9 Intranet site I manage. The site's IIS and SQL are hosted with our IT cluster. I manage the site remotely, doing updates via the site itself. Files for the site are additionally uploaded using the VPN/SFTP. This process has been fine for several years!

Now...the Division I work for, has had a corporate infrastructure change.  They are now 3 Divisions. I have registered the 3 new domains names. Requested IT to create a backup of the database and restore it to 3 new databases. The plan is to copy the old site to each of the new sites created on IIS and attach the 3 databases accordingly...then set the connection/s to the database for each site. All the PortalAlias's were also changed in SQL accordingly! This is a SQL server in the same farm.

Started up the sites with the new URL...get back a DotNetNuke:

 Error: invalidURl : The host name could not be parsed!

 Does changing the database HTTPPortalAlias on SQL ...get reflected on the physical site?  If not!!! How can I change this after the sites been copied? 

This may not even be the problem. Can you help me resolve this problem!  Their IIS is Windows 2008 IIS 7 R2

Darryl Peterson