Question

I’ve several long-standing apps written in Delphi that persist their settings in the registry. I’ve used HKEY_LOCAL_MACHINE for ‘hard’ settings such as configuration preferences and HKEY_CURRENT_USER for ‘soft’ info such as window positions, MRU lists etc.

Now my users are telling me that in non-admin (standard user) mode the apps dont work. Looking, I see that I’m not able to read a setting put into HKEY_LOCAL_MACHINE when the app was in admin mode.

What are my options for this? I know little about standard mode and how this affects access to the registry at all. Any info appreciated.

Answer 1

You can read from HKLM as a non-admin user; you just can’t write to it.

Use TRegistry.Create(KEY_READ) when constructing it, and set the RootKey to HKLM.

var
  Reg: TRegistry;
begin
  Reg := TRegistry.Create(KEY_READ)
  try
    Reg.RootKey := HKLM;
    // Read value here
  finally
    Reg.Free;
  end;
end;

You can also use TRegistry.OpenKeyReadOnly() when opening a specific registry key; this helps with non-admin access to areas of the registry as well.