PRB: Run-Time Error After an ActiveX Server Crashes

• Microsoft Visual Basic Learning, Professional, and Enterprise Editions for Windows, versions 5.0, 6.0

SYMPTOMS

If an ActiveX Server (EXE) object is instantiated in a Visual Basic client application, and the ActiveX server crashes, Visual Basic 5.0 and Visual Basic 6.0 will return the following error messages, respectively, every time the server object is subsequently referenced:

Run-time Error '-2147023174 (800706ba)':
Automation Error

Run-time Error '462':
The remote server machine does not exist or is unavailable

CAUSE

After the ActiveX server crashes, Visual Basic attempts to re-establish a connection to the server and the above error is triggered.

RESOLUTION

For Visual Basic 6.0, if you modify the code in step 4 of the "Create the Client" steps below, the error does not occur:

Private Sub Command1_Click()
   On Error GoTo ErrHand
   Set clsTest = New Class1
   clsTest.Test
   Exit Sub
ErrHand:
   Set clsTest = Nothing
   Resume
End Sub 

STATUS

This behavior is by design.

MORE INFORMATION

Steps to Reproduce Behavior

Create the Server

1. Launch Visual Basic and create a new ActiveX EXE project. Class1 is created by default.



2. Paste the following code into the code window:




      Option Explicit
      Public Event SomeEvent()

      Public Sub Test()
         MsgBox "Test"
         RaiseEvent SomeEvent
      End Sub
 

3. Select Make Project1.exe from the File menu to compile the ActiveX EXE.

Create the Client

1. Create a new Standard EXE project. Form1 is created by default.



2. In the Properties window, change the Name Property of the project to "Client."



3. Select References from the Project menu, and check Project1.



4. In Client, add a CommandButton (Command1) to Form1 and paste the following code into the code module for Form1:




      Option Explicit
      Dim WithEvents clsTest As Class1

      Private Sub Command1_Click()
         Set clsTest  = New Class1
         clsTest.Test
      End Sub

      Private Sub clsTest_SomeEvent()
         MsgBox "SomeEvent"
      End Sub
 

5. Press the F5 key to run the project and click on Command1.



6. Message boxes "Test" and "SomeEvent" pop up subsequently. Click OK on both MessageBoxes to close them.



7. Press the CTRL+ALT+DEL key combination to bring up the Task Manager.



8. Under Windows NT4, Select the Processes tab, scroll down the list, and browse for the name of the ActiveX EXE server, Project1. Select it and click the End Process button. Under Windows 95 or Windows 98, select Project1 from the program list and click the End Task button.



9. Go back to the running Visual Basic client and click on Command1. Either of the two error messages (depending on the version of Visual Basic used) mentioned in the Symptoms section above occurs.

Additional query words:

Keywords : kbnokeyword kbActiveX kbVBp500 kbVBp600 kbGrpVBDB kbDSupport
Version : WINDOWS:5.0,6.0
Platform : WINDOWS
Issue type : kbprb