Microsoft Outlook does not receive a response from Microsoft Exchange RPC Client Access service (MSExchangeRPC) for about 10 seconds. This issue may occur when the attached file has corruption. Additionally, you may receive event ID 4999 that contains the following description information:
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
This issue occurs because an InvalidOperationException exception is thrown in the MapiAttachmentProvider.OpenAttachment() function. Then, Windows Error Reporting (WER) starts to work on the exception. Therefore, MSExchangeRPC freezes for about 10 seconds until WER returns control.For more information about Windows Error Reporting, go to the following Microsoft websites: