I have found Safari 3 to be very stable with only the occassional unexpected quit. I got those with the other versions too.
No problem with Acrobat reader that I recall but I note that I am using version 8.1.0
AA does seem to be slower overall just recently, not just inside Safari. I find it quicker to launch Preview and read PDF documents from there.
I guess you have tried the usual first aid for problems like this? Disk Permissions & First Aid.
P
Are others having problems since doing this?
In order to use Adobe Acrobat I had to install latest version, Adobe Acrobat 8.1.0
Am having some unexpected drops of Safari.
Have gone from (& all since these installs) no response for Adobe Acrobat PDFs, to clicking & not having the AA plug ins recognized, to actually having things work after repeated attempts.
Any word about the Safari 3.0.3 being buggy?
Should 3.0.3 have recognized existing Acrobat or was new install required?
Sorry, I am rather a technophobe rather than technophile.

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