I have created a .rdl file which joins two data sets. In this report, there is a Grid with a column named IdentityId that has a lookup expression:
=Lookup(Fields!IdentityId.Value,Fields!Id.Value, Fields!NickName.Value, "همه_هویت_ها")
But when I try to add another column to the Grid, Report Designer resets the expression value back into:
The sample .rdl file is attached. Notice that the lookup expression is fine and works as expected in preview mode but I can no longer change the report because grid resets that lookup expression to the default field expression. You can reproduce it with the designer in installation samples. When it is hosted on IIS Express, everything is fine, but in IIS 10 this bug reproduces.
I'm running this sample on Windows 10 x64, .NET 4.5.2 and Report Designer version 184.108.40.206
Thanks in advance.