blocking all web-based emails

[waqas373]

salam

actually i want to block all type of upload and download on my network
but the real problem of how can i block the web-based emails like yahoo,hotmail and etc etc

i have 50 + users and using linux and windows both now using ISA server for proxy but after 2 or 3 weeks we migrate to squid

so give me the solution of both ISA and Squid

REGARDS
WAQAS AHMED

[LinuxFreaK]

Dear waqas373,
Salam,

Please Check the following link

http://www.linuxpakistan.net/forum2x/vi ... .php?t=414
http://www.linuxpakistan.net/forum2x/vi ... php?t=1398
http://www.linuxpakistan.net/forum2x/vi ... php?t=1130

Best Regards.