Product:
Cognos TM1 10.2.2
Windows Server 2008 R2 64 bit

Problem:
After change to use DNS alias to surf to the Cognos servers there is an error message after you try to login that says;
The TM1Web service parameter was not specified or is not one of the configured locations
You can login if you enter the TM1 server direct like this;
http://servername.domain.com:9510/tm1web/

Possible solution:
You need to update the TM1WEB.HTML file with the DNS alias.
Open the TM1WEB.HTML file from your Cognos BI gateway server in folder
C:\Program Files\ibm\cognos\c10_64\webcontent\tm1\web\tm1web.html

Update the value below by adding the DNS alias for the TM1 server.
// Update the following to point to the location of the TM1Web service(s)
var tm1webServices = [“http://servername.domain.com:9510″,”http://dnsalias.domain.com:9510”];

Save the file, and start Internet Explorer to test again.