Redmine

Hi,
I have an installation i have recently upgraded from 3.3 to latest.
Some users now have an issue where they cannot see any project from the projects, or my page links at the top of the page.
However, they can jump to a project, but then are faced with no issues viewable.
If i make a user an admin (I'm just testing at this point), then i can see they have well over 200 issues they are involved in, and the projects etc all come up fine.

Is this an upgrade issue? Is this a permissions thing?
Apparently (i'm not on site, so i'm testing over an ssh tunnel) but logging in using this account using another PC works fine.

Any suggestions? i'm not sure what files i could post to help.

Thanks
Grant