ACC: "Invalid Use of Null" with SysCmd() Function

MORE INFORMATION

The only Access Basic data type that can hold a null value is the Variant data type. Since the SysCmd() function frequently returns a null value, the return variable should have the Variant data type, as in the following example:

   Dim ReturnVal As Variant
   ReturnVal = SysCmd(4, "Status Bar Text Message")
				

NOTE: In Microsoft Access version 2.0, you can replace the "4" in the above example with "SYSCMD_SETSTATUS" (a new constant in version 2.0).

If you do not explicitly declare the return variable's data type, it is implicitly declared as a Variant data type, so the following example works as well:

   Dim ReturnVal
   ReturnVal = SysCmd(4, "Status Bar Text Message")
				

Steps to Reproduce Behavior

1. Start Microsoft Access and open any database.
2. Create a new module and enter the following line in the module's Declarations section:
   

         Option Explicit
   						

3. Enter the following code in the module:
   

         Sub SysCmdDemo1 ()
            Dim ReturnVal As Integer
            ReturnVal = SysCmd(4, "SysCmd Fails")
         End Sub
   						

4. From the View menu, choose Immediate Window.
5. Type the following line in the Immediate window and then press ENTER:
   
   SysCmdDemo1
   
   You receive the error message stated above.