OK at home, non connect issues traveling?

HI
Have an older laptopI use only for webbrowsing and mail when traveling.
I use it at home with the adapter (Router D-Link) normally to keepup the win upgrades and occasional mail check. NO PROBLEMS
Just returned from a trip, could not establish wireless connections on any of the places (hotels, Paneras, Public Libraries,etc)
Thinking maybe the adapter went bad I purchased a new Linsky adapter, installed with the CD software included, install was fine, recognized the adapter but again failed to establish a working connection ( could see what networks were available, good to excellent power)
On return home my Airlink works fine???
Weird, any help appreciated.
David

Toshiba Satellite
Intel Celeron 1.10 GHz
500 Ram
Win XP Home Service Pack2
Wireless Cardbus Adapter Airlink 101 802.11 G