How to prevent office 2007 from opening an *.xls file?

Question

I recently installed Office 2007, parallel to Office 2003, so they coexist :)

The thing I didn't anticipate is, that Office 2007 will bruteforce its way around.

I don't want it to open old (*.xls - excel 2003) files, just it's own, *.xlsx files.

I tried changing the default program, but it just points to excel.exe, and continues to use excel 2007, even though I clearly pointed it to use ..office\office11\excel.exe path, instead of ..\office2007\office12\excel.exe.

I tried this http://bensullins.com/excel-tip-defaulting-to-non-compatibility-mode/ to no avail.

Any way I can tame the beast?

Answer 1

Ok... I admit I was so frustrated I rushed into asking the Internet for help :)

I experimented a little, and what worked for me (windows 7 ultimate, 64bit SP1) was repairing your Office 2003 installation!

Control Panel -> Programs And Features -> find Office 2003 -> Repair. It may ask for an installation CD.

This should helped those who have problems with macros or VB code that was done in Office 2003, but won't work in 2007 or later for some reason.