Blackberry Sync

[#1]

Hi
My son's Blackberry won't sync with his lap top.  He can do a back up and so on, but when he clicks on sync, it says he needs to connect to the internet (he is connected to the internet).  I wondered if it was because he didn't have an email program installed ( ::)) so put TBird on it.  Then I looked to see if there was anywhere to point it towards the right program, but there isn't anywhere that I can see, so presumably the Blackberry automatically detects the email program, address book and calendar.
I wondered if it was that he uses Google mail (which he gets on the Blackberry ok), and generally uses it on webmail, but I can't see why that would be a problem once Thunderbird is installed, and his Google mail pop3 account set up. 
John

[#2]

Hi
It's a long shot, but I had a similar problem after installing the PC Suite for my Sony Ericson phone.
That seemed to change my internet connection settings, so I had to change them back again.
On XP, you would go to Control Panel / Internet Options, click ont he Connections tab, then click on the "never dial a connection" button, then click OK.
There's a similar setting for Vista / 7, but I don't have one to hand right now to check.

[#3]

Thanks for the response.  I've had a look in Internet Options, and there is nothing in there (therefore no option to tick that box). No internet accounts, since of course he connects via my wireless network.
John