A few days back I’ve got the error message “webform_dopostbackwithoptions is undefined” on the project that i’m working on.
The strange thing it happened only when I activated the securepagemodule, when i deactivated the module it works perfectly. I tried to debug it with HTTP debugger (fiddler tool) and i found that on that particular page, there is a request from webresources.axd but the request is not into https but into http and what i believe since the page is on secure mode therefore it discards the “webresources.axd” since it’s not secure. The workaround for this issue is by adding entry of “webresources.axd” under securepage and the problem is solved.
This is the sample of web.config for it
NOTE:This is resolved in the new version of securepage module