Iis – “405 Method Not Allowed” occurs on production server, fine on development server

I am currently experiencing a strange discrepancy between our development and production servers. The issue is related to a jquery call to a WebMethod/ScriptMethod located on an aspx page, as per Dave Ward's technique.

On our development server, which is on an internally-accessible Windows Server 2008 box running IIS 7, the call works as intended from any given machine within the network.

Unfortunately, when we pushed this build to production server, which also uses Windows Server 2008 w/ IIS 7 we immediately began receiving a "405 Method Not Allowed" exception.

There are no special handler mappings or url rewriting modules/techniques being used, which seems to be the trend in a lot of similar problems found by searching in SO. The web.config between the two is also identical, save a couple connectionStrings.

Any nudge in the right direction would be very greatly appreciated!