Wireless Connected but Unable to Surf

I have a Compaq Presario running XP and has the wireless connection which worked fine until I brought it to work and had the tech guy put the info in so that I could connect to the secured connection here wirelessly which works fine but not when I go to the coffee shop which had free access. I can still connect with an excellant signal but when I open Internet Explorer it says Unable to disply this web page also in my Windows live messanger when I do the trouble shooting it stops with a yeild sign at the Default Gateway. The tech guy said he did put in a default gateway for the connection at work and told me to go in under the wireless connection to the properties to TCP/IP in advanced and remove the Default Gateway which I did and it still won't "connect " to the internet ! What do I do now as I said before I had no problems. This is driving me crazy as I use this laptop to travel and can not connect to the internet anyplace. No problems connecting to wireless networks but can't get onto the internet!! Please Help! Private e-mails are more than welcome!!!

 

Were there any other settings typed in that TCP/IP settings dialog? Set it to 'Obtain an Address Automatically'