Ever since I added the Google tool bar to the Explorer window on my
computer, those very annoting pop-ups have been blocked, 56 of them to
date. That pleases me very much. However, I have one concern. By
blocking all pop-ups am I also unwittingly blocking legitimate
notifications from Microsoft, Norton and other software suppliers like
Adobe and Epson about upgrades and other information I need to have to
keep my computer up to date and protected from harmful viruses?

Hi pangur,

If you use the Google Bar pop-up blocker, the only 'pop-ups' that it
will block are web page popups. Things like a Microsoft Update notice
that there are new updates waiting to be installed or a message from
your Virus software that tells you that you should update your virus
definitions are NOT blocked by the toolbar. Such popups are 'System
Messages' and entirely seperate from a website.

However, there are some popups on websites that may be of use: for
example, coupon codes are commonly found in popups as are 'special
offers' that have a limited time duration. Using Google's popup
blocker will (of course) block the good popups on legitimate sites as
well as the bad popups on sites.

Google has a page devoted to describing the usage of the toolbar. You
can find the quick documentation here:
http://toolbar.google.com/popup_help.html

You may wish to pay special attention to this part of the document:
"Sometimes sites communicate useful information via pop-up windows.
The pop-up blocker can be told to remember these sites so pop-up
windows are allowed to launch. This information is stored on your
computer in what's known as a "whitelist" (as opposed to a
"blacklist"). The pop-up blocker uses the whitelist to turn itself off
when you visit sites whose pop-ups you don't mind viewing.

As you find sites that have pop-ups you want to see, click the pop-up
blocker button to add that site to your whitelist. (The whitelist is
never actually displayed.) Repeat this process as you find websites
where you want to see pop-ups."

I hope this information answers your question. If you have any
questions, please ask for clarification prior to rating and closing
this question.

Thanks,

Legolas-ga

No search used: simply navigated the Toolbar's help system.