Steps to reproduce:
1. Add a grid to a form and make it read only
2. Add a masked box column and set the mask
3. Add some data and run the project
You will see that the mask is not applied to the values in the mask box column
Comment: This is not an issue.  The mask is applied after editing the text with RadMaskedEditBox, in read-only mode there is no masked editor created. You should use the conversion layer in RadGridView to solve the issue. Check the GridView >> Manipulated Data >> Convert Values example from our demo application.