If you are new to Vista like myself, one of the irritation will be to deal with permission issues with files in Program Files.
After installing Zend Core in the Program Files folder (which is the default setting), I find that I cannot create folders inside ‘htdocs’.
Apparently, Vista has some new protective feature that tries to be smart and disallowed changes to stuffs under the Program Files directory.
The easy way to solve this is just to uninstall Zend Core, Apache or whatever programs that encounter this issue and install it in a folder outside of it.
You can choose a separate drive eg. D:\ or even in your user directory.
Vista, in my opinion, is one version that provides no little benefit to the users. Not really worth the upgrade unless it comes with a new machine.
And even if it comes with a new machine, be prepared for a culture shock. Things that can be done in XP may not hold true with this version.