Hi,
I am having the exact same problem, and have done what you suggested here, and reset Safari, but still no change.
any other ideas? I am not sure exactly when this happened, but here is what I was doing just before I realised the problem, I think it was the effect of one of these two, if that makes sense:
1. Playing around with the permission settings of a folder (on ~/sites/mysite) changed the permission settings to read+write for access group and others and chose "Apply to enclodes items"
2. Was trying to view an XML file I was working on and was getting error messages for viewing the file in Safari (error in XML)
the error message I get when trying to open any webpage:
"Safari cant open the page
http://news.bbc.co.uk/”. The error was: POSIX error: Cannot allocate memory (NSPOSIXErrorDomain:12) Please choose Report Bug to Apple from the Safari menu, note the error number, and describe what you did before you saw this message."
would really appreciate any help, I'm really getting desperate. btw, I upgraded to tiger from osx 10.3.9 a few weeks ago and my current version is 10.4.2.