Safari unstable

Question

While I have Firefox, I find it mind bogglingly too slow, so use Safari 5.1.5 for general daily web use.
Recently Safari has become sluggish and very unstable. I can't for example log into Apple support communities (had to use Firefox for this posting), my e-mail account, and so on. When Safari is running the entire machine slows down considerably too; rebooting - then not using Safari is the only solution I have found at present. I have used Webkit, but I believe that runs on the back of Safari, so even webkit is now unstable too.
Emptying the cashe, resetting, all seem unable to resolve the issue.
The problem seems to date back to downloading 5.1.5, but that may just be coincidence. The issues seems specific to Safari and it's impact when running.
I am considering which Safari files to delete from the 'Users' folder and reinstalling Safari; but just wondered if others had the same experiences or a solution?
Any ideas to point me in the right direction welcome.

Answer 1

Back up all data if you haven’t already done so. Before proceeding, you must be sure you can restore your system to the state it’s in now.
Last warning: DO NOTHING unless you have a backup and you know you can restore from it.
Read this whole message before doing anything.
Quit Safari if it’s running.
Step 1
In the Finder, press the key combination shift-command-A to open the Applications folder. Select the Safari icon in that folder and press the key combination command-I to open the Info window. There’s a checkbox in the Info window labeled Open in 32-bit mode. If that box is checked, uncheck it. Close the Info window and the Applications folder.
Open the Library folder in your home folder as follows:
☞ If running Mac OS X 10.7 or later, hold down the option key and select Go ▹ Library from the Finder menu bar.
☞ If running an older version of Mac OS X, select Go ▹ Go to Folder… from the Finder menu bar and enter “~/Library” (without the quotes) in the text box that opens.
Delete the following items from the Library folder (some may not exist):
Caches/com.apple.Safari
Caches/com.apple.WebKit.PluginProcess
Caches/Metadata/Safari
Preferences/com.apple.WebKit.PluginProcess.plist
Saved Application State/com.apple.Safari.savedState
Leave the Library folder open. Try Safari again. If it works now, stop here. Close the Library folder.
Step 2
If Safari still doesn’t work right, quit, go back to the Finder and move the following items from the open Library folder to the Desktop (some may not exist):
Cookies/Cookies.binarycookies
Cookies/Cookies.plist
Preferences/com.apple.Safari.LSSharedFileList.plist
Preferences/com.apple.Safari.plist
Preferences/com.apple.Safari.RSS.plist
PubSub/Database
Safari
(Note: you are not moving the Safari application. You’re moving a folder named “Safari.”)
Try again. This time Safari should perform normally, but your settings and bookmarks will be lost.
If the issue is still not resolved, quit Safari again and put all the items you moved to the Desktop back where they were, overwriting the newer ones that will have been created in their place. You don’t need to replace the files you deleted in step 1. Stop here and post again.
If Safari is now working normally (apart from the lost settings), look inside the “Safari” folder on the Desktop for a file named “Bookmarks.plist”. Select File ▹ Import Bookmarks from the Safari menu bar. Import from that file. Recreate the rest of your Safari settings. You can then delete the items you moved to the Desktop.
Note: This step will remove your Safari Extensions, if any, and their settings. If you choose to restore them, do so one at a time, testing after each step to make sure you haven’t restored the problem.
If you don’t like the results of step 2, you can undo it completely by quitting Safari and restoring the items you moved or deleted in that step from your backup, overwriting any that were created in their place. If you followed these instructions, you have a working backup and you know how to restore from it. If you didn’t follow the instructions, I can’t help.