We have an app that using Windows logon info for single sign-on to the app.  Even though Windows is not case sensitive, the app is.  So if the user ID is not in the correct case of upper and lowercase letter, the app doesn't work.

I noticed when a user signs into their Windows 8.1 computer, even though they typed capital letters into their user ID field, Windows automatically switches the user name back to all lowercase.

How can we fix this?

Windows apps can only be downloaded from Windows Store via Microsoft Accounts, which are users specific. If they have to access stores then they have to use their Microsoft log in credentials which are not in Caps.

I didn't mean a Windows Store app.  

This is a domain user logging into Windows using their domain credentials.  The legacy x86 application with the issue is case sensitive with it's single sign on integration and obtains authentication from the user's Windows login.

• Edited by MyGposts 3 hours 52 minutes ago

I didn't mean a Windows Store app.  

This is a domain user logging into Windows using their domain credentials.  The legacy x86 application with the issue is case sensitive with it's single sign on integration and obtains authentication from the user's Windows login.

• Edited by MyGposts Wednesday, July 22, 2015 3:29 AM

I didn't mean a Windows Store app.  

This is a domain user logging into Windows using their domain credentials.  The legacy x86 application with the issue is case sensitive with it's single sign on integration and obtains authentication from the user's Windows login.

• Edited by MyGposts Wednesday, July 22, 2015 3:29 AM

Hi MyGposts,

I found a registry key related to case sensitive.
 HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\kernel\obcaseinsensitive
Change its value to "0".
I hope it will be useful.

Best regards