Cannot sign-in to forums in IE 11

Question

When I attempt to sign-in in forums (Visual FoxPro forum) by clicking Reply link in any question following error appears:
Server Error in '/Forums' Application.
Runtime Error
Description: An application error occurred on the server. The current custom error settings for this application prevent the details of the application error from being viewed remotely (for security reasons). It could, however,
be viewed by browsers running on the local server machine.
Details: To enable the details of this specific error message to be viewable on remote machines, please create a <customErrors> tag within a "web.config" configuration file located in the root directory of the current web application.
This <customErrors> tag should then have its "mode" attribute set to "Off".
<!-- Web.Config Configuration File -->
<configuration>
<system.web>
<customErrors mode="Off"/>
</system.web>
</configuration>
Notes: The current error page you are seeing can be replaced by a custom error page by modifying the "defaultRedirect" attribute of the application's <customErrors> configuration tag to point to a custom error page URL.
<!-- Web.Config Configuration File -->
<configuration>
<system.web>
<customErrors mode="RemoteOnly" defaultRedirect="mycustompage.htm"/>
</system.web>
</configuration>
The work around is Google Chrome...
To sign-in on e.g. MSDN page is possible but when I try the below forums link above error appears again.
https://social.msdn.microsoft.com/Forums/en-US/home?forum=visualfoxprogeneral&stoAI=10&wa=wsignin1.0
IE 11 version: 11.0.9600.16476, update 11.0.2
Windows 7/64 Home Premium SP 1

Answer 1

This is not problem of Visual FoxPro forum but the link "Sign-in" does not work properly on all forums - above Server error is reported after each attempt to sign-in.
When I switch to MSDN Subscriptions page then I can sign-in. BUT when I enter the forums link after successful sign-in  (http://social.msdn.microsoft.com/Forums/en-US/home)
the error appears again...  The only possibility how to enter forums web is to click on some particular thread link somewhere in my mail... (or Google Chrome, of course).
The problem started (probably) after the new MSDN subscription activation the last week.