Hello,
From some time ago we have been experiencing on our project machines being stuck due to some performance issue of Excel which loads files (even small) too long. What our bot does is export of data from a transaction in SAP GUI to an Excel Workbook. Then, the bot applies 'Attach to workbook' Action from the original MS Excel VBO object (which in fact invokes Open Instance Action). From time to time, the bot gets stuck at this Action. Probably it tries to attach to the Workbook before Excel is ready and that's the reason but we have no idea how to fix it. There are some other errors which get thrown like:
Internal : Could not execute code stage because exception thrown by code stage: The message filter indicated that the application is busy. (Exception from HRESULT: 0x8001010A (RPC_E_SERVERCALL_RETRYLATER))
It may be solved by a retry loop or, in a more sophisticated way, by using IMessageFilter::RetryRejectedCall. It happens in the global code, function OpenNamedObjectAA (line generating the error: Dim application As Object = workBook.Application)
Public Function OpenNamedObjectAA(workbookName As String) As Object
Const OBJID_NATIVEOM = &HFFFFFFF0
Dim IID_DISPATCH As New Guid("00020400-0000-0000-C000-000000000046")
Dim workBook As Object = Nothing
Do
Dim XLhwnd As IntPtr = FindWindowEx(IntPtr.Zero, XLhwnd, "XLMAIN", Nothing)
If IntPtr.Equals(XLhwnd, IntPtr.Zero) Then Exit Do
Dim XLDESKhwnd As IntPtr = FindWindowEx(XLhwnd, IntPtr.Zero, "XLDESK", Nothing)
Dim WBhwnd As IntPtr = FindWindowEx(XLDESKhwnd, IntPtr.Zero, "EXCEL7", Nothing)
AccessibleObjectFromWindow(WBhwnd, OBJID_NATIVEOM, IID_DISPATCH, workBook)
If workBook IsNot Nothing Then
Dim application As Object = workBook.Application
If application IsNot Nothing Then
Try
application.Windows(workbookName).Activate()
Return application
Catch ex As Exception
Continue Do
End Try
End If
End If
Loop
Throw new Exception("Excel with workbook name '" & workBookName & "' not found.")
End Function
However, we are still not sure about the origin of the main problem discussed here - freeze of Blue Prism at the Action Open Instance and how to solve it. Do you have similar experience and know how to help us in this matter?
It is worth being added that the OpenNamedObjectAA function is invoked asynchronously by this code (OpenNamedObjectAA is the Operation😞
Private Function ExecWithTimeout(Of T)(timeout As Integer, name As String, operation As Func(Of T)) As T
Dim ar = operation.BeginInvoke(Nothing, Nothing)
If Not ar.AsyncWaitHandle.WaitOne(TimeSpan.FromSeconds(timeout)) Then
Throw New TimeoutException(name & " took more than " & timeout & " secs.")
End If
return operation.EndInvoke(ar)
End Function
