Interestingly Firefox does not understand start (*) in bypass proxy "No Proxy for:" textbox. Somewhere I came to know the notation which works fine for FIREFOX! its not a great discovery and there is an example given below "No Proxy For:" 192.168.1.0/24 However sooo many pepole don't know what is the meaning of 192.168.1.0/24. So this how we can utilize that - 1. 101.222.*.* - means first two fields are fixed. 2 (First 2 fixed fields) x 8 = 16. So you can use 101.222.0.0/16 instead of 101.222.*.* 102.*.*.* - means first field is fixed. 1(First fixed field) x 8 = 8. You can use 102.0.0.0/8 instead of 102.*.*.* Simple! It just works Cheers,