Hello LiveIt24Seven,

the AVG Toolbar can be updated independently to make it compatible with Firefox 4 (providing the toolbar is installed in an older Firefox version currently):
- Open your Firefox.
- Click the small black triangle next to the "AVG" logo and select "Update".
- Wait for the update to be finished.
Now, you can upgrade the Firefox to 4.0 and the toolbar will be still present there. Please note however, the Search-Shield (evaluating search results with icons) won't be functional until the following AVG program update.

Thank you.