The following error is displayed when a theme is upgraded
Theme Designer cannot upgrade a theme because the 'x' namespace prefix is not defined in certain files
Answers approved by DevExpress Support
We have fixed the issue described in this ticket and will include the fix in our next maintenance update. To apply this solution before the official update, request a hotfix by clicking the corresponding link for product versions you require.
Note: Hotfixes may be unavailable for beta versions and updates that are about to be released.
We have fixed this error in the latest Theme Designer update. You can obtain the offline installer at https://github.com/DevExpress/wpf-themedesigner-app/releases/latest or update your Theme Designer on the About page of the start screen.
Hello,
Version 18.1 and 19.1 are only versions of the WPF Theme Designer tool and aren't related to our controls. So, if you uninstall WPF Theme Designer of version 18.1 and install WPF Theme Designer of version 19.1, you will still be able to create and edit custom themes of version 17.1.8 and higher.
Thanks,
Kirill