[TYPO3-windows] random pages show 500 error

[Pim Broens - Redkiwi]

Hi All, 
 
I'm having some issues with a TYPO3 installation on a windows IIS 7.
Basically, on random pages I get a 500 error. And all I have to do to
solve it is checking the 'no_cache' checkbox in the page properties.
I've tried copying the page and then there is no problem showing it and
even caching it.
I've tried setting up a new TS template there and only showing some text
via page = PAGE, page.10 = TEXT etc.. But that still gave me a 500
error.

Anybody has a clue to where I should start looking?

Kind regards,
Pim Broens