POST request coming from HTML page, <form method = post/>. to abc.ashx handler added to DNN9 with 2 portals ID 0,1. Request coming to portal 0, but username to be logged found in portal1. DNN successfully processing request, Login user to portal 1 and redirects portal 1 home page. .DOTNETNUKE cookie returned to the caller's browser. Close browser (or not) and make another request from the same http file. Fiddler shows POST request, but it's not coming to abc.ashx handler. It's changed to GET to Default.aspx. , response 'object moved' to browser and kills .DOTNETNUKE. Next POST will be successful again because cookie is removed. However everything works properly if POST made to portal 1 directly, i.e. no portal changes.

Question/s: what module changes request from POST to GET? Why 2nd request is not going through what user logged to the portal? How we can work around