Need Help

Problems accessing tabs in control panel etc [Solved]

upgraded from version 20061201_yacs_6.10.tgz to 20081130_yacs_8.11RC30.tgz

WorkflowSupport request
StatusImmediate solution has been provided
I had an older site running and upgraded as written above in 2 steps to newest version. All looks / works fine except I can't access the various tabs in the control panel and in the user "edit profile" page.

Any fix you can suggest?