Morris, welcome to the Vista x64 Forums
I've been doing some reading about your issue. There is some discussion about potential solutions.
1. If you're running any AV software, disable it, specifically Norton or Symantec.
2. Depending on your adapter, you may have to either update to the newest driver, or roll back to an older version.
Check on these potential issues and let us know if either of them help your situation. If not, we can continue to examine the issue, just let us know what your AV software is and what kind of adapter and router you are using.