Win7 through a PIX 506 firewall

[snbaker]

I've got a Cisco PIX 506 firewall that only allows traffic to certain sites with my PCs running Win7 on my small office network. I'm sure it's a firewall issue as I've disconnected the firewall and went directly to my ISP (Cox) and had no problems. What settings must I change on my firewall or on Win7 to get it to work with my PIX 506?

 

[Desslok]

I think the issue is related to the Scaling where it tries to auto-tune teh MTU.

 

[snbaker]

Thanks for your reply. I'm not an expert so can you direct me as to how I could check this or make a change? I know MTU has to do with packet movement but is that changed in Win7 or on the firewall? Thanks!

 

[Desslok]

Try this open an elevated CMD prompt, then type:
netsh int tcp set heuristics disabled <enter>
netsh int tcp set global autotuninglevel=disabled <enter>


See if that helps

 

[snbaker]

No go on that suggestion. Anything else I could try?