I was looking at info for customizing phpbb. Tried this query on Google:
+"powered by phpbb"

Got this error message:
------------
Google Error 403

We're sorry...
... but we can't process your request right now. A computer virus or spyware application is sending us automated requests, and it appears that your computer or network has been infected.

We'll restore your access as quickly as possible, so try again soon. In the meantime, you might want to run a virus checker or spyware remover to make sure that your computer is free of viruses and other spurious software.

We apologize for the inconvenience, and hope we'll see you again on Google.
------------

Any other query seems to work fine including: +"powered by php"
Just having the phpbb word in that query seems to produce this 403.
Does anyone see the same thing? I have a virus utility running on my machine (McAffee).

You can try this link: google search test (http://www.google.com/search?sourceid=navclient&ie=UTF-8&rls=GGLD,GGLD:2003-47,GGLD:en&q=%2B%22powered+by+phpbb%22)

Maybe it's just a temporary thing on my pc...

Yea, I covered this (http://www.seroundtable.com/archives/001635.html) yesterday based on a thread at WebmasterWorld (http://www.webmasterworld.com/forum30/28417.htm).

GoogleGuy responded to it stating:
That page originally started because when someone has a virus or a trojaned machine, they often don't realize that their machine may be sending queries to Google without them asking. :)

Recently, we've started to improve the software, and it can also detect lots of things like rank checking and other automatic queries to Google. Of course, we don't show the message to everybody that comes onto our radar, but our new software looks pretty good at detecting programmatic queries. If you're using WebPosition or other software that sends queries to Google from a program, I'm not surprised if you're going over a threshold where your queries are on the radar.

If you do see this message, I would recommend not sending so many queries to Google--the volume or type of queries are unusual enough that it's attracting greater scrutiny from us. If you avoid sending queries to Google from a program, you'll be as right as rain.

ok. I guess they must have a filter for the query "powered by phpbb" that might be used by software that runs automated queries. That would explain it.
Thanks

It looks due to the Santy worm (http://www.threadwatch.org/node/840) that wreaked havoc last December - looks like Google have left a block on that specific search term to protect against following variants using Google search to locate targets.

Odd to see it though - are they actually still under attack? Suggesting that the user machine is infected does seem a little irresponsible, though. It's a blocked search query, not a user machine infection.