Please do the following.

• In the location bar, type about:config and hit Enter.
  
  
• In the filter at the top, type: keyword.URL
  
  
• Double click it and remove http://search.sweetim.com/search.asp?src=2&q= and replace it with http://www.google.com/search?q=
  
  

The URL to add in "keyword.URL" becomes a link in this post, so right click it and choose "Copy Link Location" to copy it to the Windows clipboard. Then hit CTRL+V to paste it. Saves you having to type the whole thing.

To reset your home page, do the following.

• Go to the site you want to set as your homepage.
  
  
• Click the orange Firefox button and go to Options | Options | General.
  
  
• Make sure it says "Show My Homepage" in the first dropdown menu.
  
  
• Click the button called "Use Current Pages" to set the homepage to the one you have on the screen.
  
  

After you complete the above steps, install this add-on to prevent another search engine from modifying your preferences: https://addons.mozilla.org/en-US/firefox/addon/browserprotect/

After you complete the above steps, open the "Add-ons" | "Extensions" menu again and remove SweetIM Toolbar if it's there.

mm. i forgot to mention that i'm not using any toolbar, including the SweetIM's. (there's one but i disabled it). but the URL part, yeah, just like what you said. i've changed it to Google. thanks a lot by the way.

Just try to install (any) new add-ons and restart firefox.

Deleting the "extensions.sqlite" file in my profile folder http://kb.mozillazine.org/Profile_folder_-_Thunderbird fixed it — be sure to make a copy of the file beforehand.

Thanks so much... It really worked!! You're brilliant!! Anyway, the sweetim thingy is not in my add on page.