setting default tabs to same sharepoint server causing issues.

We recently consolidated our separate SharePoint sites to one corporate SharePoint farm .   Corporate has their site as the primary landing page. To get to my divisional sites quickly, rather than navigating from the corporate landing page, i added the 2 additional tabs at startup on the client browser side to our local SharePoint page(s).   Since then, when i open the browser, it seems like the corporate SharePoint server is getting confused when authenticating (Single Sign on) each of the pages, eventually times out, or doesn't display tabs, or show 3 of the same page.. all kinds of weirdness. Or just closing the browser a couple times fixes it..  not all the time though. 

can you help me out?