Solved

RPC detected an integrity violation while decrypting an incoming message

Posted on 2013-05-30
4
923 Views
Last Modified: 2013-09-10
Hello everyone,

We have an issue in one of our offices, there are 12 users with identical Outlook setups.

5 of these 12 suddenly started having severe problems with Outlook constantly disconnecting and reconnecting, failing to correctly synchronize folders and failing to send messages. The event log on the client PC didn't reflect anything useful and the only thing we could find on the Exchange server was this error in the Security log:

4816: RPC detected an integrity violation while decrypting an incoming message

RPC requirement is set to False on the server (this is a default setting in Exchange SP1). But Outlook by default encrypts messages so it appears that the Exchange is failing to decrypt these messages. The error message goes on to provide a source IP address for the problem and these all match the specific users with the issue.

Unticking encryption in the affected Outlook profiles is a workaround for the issue, but obviously as many other users are set by default to encrypt, we need to fix the root issue of the Exchange failing to decrypt to prevent issues popping up in future.

We have searched high and low on Google with little mention of this issue.

We are running Exchange SP1 on Server 2008 R2. Client PCs are Windows 7 and Outlook 2010.

Any help would be appreciated.
0
Comment
Question by:Auckland
  • 2
  • 2
4 Comments
 
LVL 63

Accepted Solution

by:
Simon Butler (Sembee) earned 500 total points
ID: 39208972
I would start by updating Exchange.
Exchange 2010 SP1 is no longer supported, you need to be on SP2 or preferably SP3.

As it is remote people my instinct is firewall. That can break the encryption in my experience.

Simon.
0
 

Author Comment

by:Auckland
ID: 39210079
Thanks Simon, we will update Exchange and see if that resolves it.

It is a remote office but with a local Exchange server, should've specified that sorry.

I'll report back once we have applied updates, thanks very much for the suggestion.
0
 

Author Comment

by:Auckland
ID: 39219771
Updated all Exchanges to SP3, still have the same issue.

When users are set to unencrypted, attachments either do not send at all or arrive in a corrupted form (JPGs arrive with distorted colours, PDFs corrupt and Excel documents arrive corrupted).

When users are set to use encrypted mode, Exchange repeatedly shows as Reconnecting, Online, Reconnecting, Online etc (in 5 second intervals) and items stick in the Outbox due to this. Incoming mail appears to work but arrives in batches presumably due to the intermittent connection.
0
 
LVL 63

Expert Comment

by:Simon Butler (Sembee)
ID: 39220711
Have you checked the network card driver is at the latest version?
Run BPA from the toolbox to confirm there is nothing else wrong?

What else is on the server? Does the AV have the correct exclusions in place?

Simon.
0

Featured Post

How to run any project with ease

Manage projects of all sizes how you want. Great for personal to-do lists, project milestones, team priorities and launch plans.
- Combine task lists, docs, spreadsheets, and chat in one
- View and edit from mobile/offline
- Cut down on emails

Join & Write a Comment

Utilizing an array to gracefully append to a list of EmailAddresses
OfficeMate Freezes on login or does not load after login credentials are input.
This tutorial will walk an individual through the steps necessary to configure their installation of BackupExec 2012 to use network shared disk space. Verify that the path to the shared storage is valid and that data can be written to that location:…
This tutorial will walk an individual through the steps necessary to install and configure the Windows Server Backup Utility. Directly connect an external storage device such as a USB drive, or CD\DVD burner: If the device is a USB drive, ensure i…

747 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

12 Experts available now in Live!

Get 1:1 Help Now