I have designated a default project in my Rally user profile, but am taken to a different project when logging into Rally.
If you are using a bookmark to access Rally, the Project OID (ObjectID) is likely to be saved in the URL that was bookmarked and will override your profile settings.
To test this, log out of your session, then manually type https://rally1.rallydev.com into your address bar and login, then you should be taken to the default project you selected for your user profile. If this resolves the issue, you will need to modify your bookmark to point to https://rally1.rallydev.com
In the case of SSO, please ensure that links to Rally from any internal landing page for the SSO environment points to https://rally1.rallydev.com. When using SSO you may need to sign out of Rally before logging in again if you were previously take to the wrong page.
Keywords: Agile Central