All links from Excel open in new window regardless of how the settings are
configured in IE. this is very frustrating, see below for steps taken so far
and versions used.

Office 2007
IE 7
IE 8

So far I set all the setting in IE to open new tab, the settings work for
all applications except excel.
I uninstalled IE 7 and installed IE 8, problem persists.
tried wheel clicking the link in excel - this does not work
tried ctrl-clicking the link in excel - this just highlights the cell.

Please help i'm confused by this one, it was working fine up until one day
last week. there are no toolbars installed in IE, it is a fresh install with
standard installation plug-ins.