Outbound URL filtering using LSP

[Andy]

Hi,

I am trying to do outbound URL filtering using LSP, basically I
checked outbound HTTP request from WSPSend and if I find the URL that
needs to be blocked, then I call WSPCloseSocket and return the error
code from that call, that works fine with Firefox, but for IE, it
always displays "Internet Explorer cannot display the webpage", which
is not I want, I want IE still displays previous page.
Anything I should change, such as return different error code, set
lpErrno to specific Winsock error code? TIA.

-Andy