Hello Sir,

Most likely this is due to the fact that your K2 Claims configuration does not currently use the reverse proxy URL. I would highly suggest going through the K2 Setup Manager for Blackpearl and SmartForms. While going through please click the bindings button on the following 3 locations. Then I would select the proper IIS site binding that pertains to your reverse proxy URL:

Blackpearl setup manager. On this page we should click the bindings button and select the correct host header binding to be used and for default:
http://help.k2.com/onlinehelp/k2blackpearl/icg/4.7/default.htm#install/manual/bp/bp_inst_workspaceweb.htm

SmartForms Setup Manager. This will have two identical looking pages, one for Designer and one for Runtime. We will do the same as the above for the blackpearl setup manager. Click bindings and choose the correct binding to be set as default:

http://help.k2.com/onlinehelp/k2blackpearl/icg/4.7/default.htm#install/manual/sf/sf_designwebsite.htm
http://help.k2.com/onlinehelp/k2blackpearl/icg/4.7/default.htm#install/manual/sf/sf_runtimewebsite.htm

For specifics you can probably confirm this by checking the Claims Configuration via your K2 Management Site. Also see the following documentation for more information:

http://help.k2.com/onlinehelp/k2five/userguide/5.0/default.htm#k2_management_site/authentication/claims.htm

Regards,

Evan

hi  @EvanM 

Thanks for your help. We have resolved it by changed the Workspace URL Value in Environment Library and reset IIS.

Best regards,