Cannot connect to the web within Matlab

I cannot open any webpage within matlab when using the web() function and I get the error: Warning - File or URL Not Found. Also, I cannot read data with the urlread() and I get the error: Error downloading URL. Your network connection may be down or your proxy settings improperly configured. I don't use a proxy. Matlab is R2010a (64bit) and my OS Windows Enterprise (64 bit). What could be the problem? Thank you in advance.

[Walter Roberson]

Windows Firewall settings problem possibly?