How to solve DSServerModule1.ClientHeight: Property does not exist error

I wrote an application that uses a firebird database, using a server and a client. I originally coded the application using Delphi XE2 and all worked fine. I have now moved over to Delphi XE6.

I recompiled the server and there was no errors, but now that I recompile the client it gives me the following error:

ProjectPiping.exe raised execption class TDBXError with message "Remote error: Error reading DSServerModule1.ClientHeight: Propery CliehtHeight does not exist.

I have read online that you need to change the dfm file ontop from Object to Inherinted but that made no difference.

Is there anyone that can assist me as I do not see anyway that I can solve this except going back to Delphi XE2

Solution

Missing property errors are common for Frames and DataModules that do not directly inherit from base Delphi TFrame and TDataModule class. Under some circumstances (that change with every Delphi version) Delphi will not be able to access Frame or DataModule ancestors in order to determine whether it deals with TFrame or TDataModule descendant. When that happens, it will wrongly interpret Frame/DataModule as Form and pollute their .dfm with Form specific properties.

You don't have to rollback to XE2 and you can fight the issue by removing bad properties from .dfm file using Notepad or similar editor. Since this is operation you will be bound to repeat often while doing design work on such Frame/DataModule, version-control can be of great help. Just don't commit changes that are not supposed to be there. Another way of fighting against sporadic changes in .dfm files is to make them read-only once you have finished your design-time work with them.

Correct empty DataModule .dfm file:

inherited DataModule1: TDataModule1
  OldCreateOrder = False
  Height = 150
  Width = 215
end

Broken empty DataModule .dfm file

object DataModule1: TDataModule1
  Left = 0
  Top = 0
  ClientHeight = 188
  ClientWidth = 303
  Color = clBtnFace
  Font.Charset = DEFAULT_CHARSET
  Font.Color = clWindowText
  Font.Height = -11
  Font.Name = 'Tahoma'
  Font.Style = []
  OldCreateOrder = False
  PixelsPerInch = 96
  TextHeight = 13
end