>>>
>>>I realy need a command I can insert into shell execute
>>
>>Maybe you can use Windows Scripting Host instead of ShellExecute, since WSH has a function called SendKeys() which you can use to send keystrokes to the activated application. See here for sample code: https://support.microsoft.com/en-us/kb/259103?wa=wsignin1.0
>
>I can't see how to use it but thanks anyway
>
>I really need a command I can insert into shell execute to disable error printing

That is not possible.
IIRC there is a flag on a bitmapped long in ShellExecuteInfo structure used by ShellExecuteEx.
That is the way to control some aspects of ShellExec, other than trying to manipulate the registry keys for the specific action verb of the file type.

rgds

thomas