Exchange Server - Exchange 2007 hidden attachments

Asked By gsmik

18-Mar-08 06:10 PM

One of our BI apps (Cognos) sends emails with PDFs attached. After moving
several users mailboxes from Exchange 2003 to Exchange 2007, these users now
receive the messages but the attachments are not visible in the message when
viewed from Outlook 2003. They can see the attachments in OWA, or if they
choose Save Attachments from the File menu in Outlook.

I found one reference to this problem on a blog post that said it would be
fixed in Exchange 2007 SP1, but our servers are already running Exchange 2007
SP1, so obviously that didn't fix the problem.

Is this a known problem? When will it be fixed? Is there a workaround, other
than the ones mentioned above?

Thanks,
Mike

18-Mar-08 11:53 PM

Hello Mike,

Thank you for posting here.

According to your description, I understand that you unable to view the PDF
attachments in Outlook after you move mailbox from Exchange 2003 to
Exchange 2007. If I have misunderstood the problem, please don't hesitate
to let me know.

Based on my research, I suggest we try the following steps to see if we can
resolve this issue:

- Open Exchange Management Console on Exchange 2007
- Under the Organization Configuration selected the Hub transport.
- On the Right pane under Transport rule tab.
- Created a new Transport rule.
- Selected the option "When any attachment file name contains text
patterns" typed .pdf
- Clicked Next under Actions Select "set header with value," click the
highlighted "header" text, type Content-Type, click OK
- Click the highlighted "value" text, type multipart/mixed, click OK, and
then click next
- On the "Exceptions" page, simply click next
- Finally "Create Rule" page, click New, then click Finish
- Restarted the Microsoft Exchange Transport service.
- Now tested the mail with PDF Attachment.

If we cannot resolve the issue after we perform the above steps, please
help me collect some information for further investigation:

1. If you send mail with PDF attachment from a normal Exchange mailbox
account, does the issue reoccur?

2. Does this issue happen on all mailbox accounts on Exchange 2007?

3. Does this issue happen when you view the email from Outlook 2007 client?

4. Please forward the problematic email to an Exchange 2003 mailbox, does
the issue still happen?

I hope these steps will give you some help.

Thanks and have a nice day!

Best regards,

Terence Liu(MSFT)

Microsoft CSS Online Newsgroup Support

Get Secure! - www.microsoft.com/security

This posting is provided "AS IS" with no warranties, and confers no rights.

--------------------
now
when
be
2007
other

21-Mar-08 07:29 AM

Try the roll up for Exchange 2007 service pack 1.

Description of Update Rollup 1 for Microsoft Exchange Server 2007
Service Pack 1
http://support.microsoft.com/?kbid=3D945684




James Chong (MVP)
MCITP | EMA; MCSE | M+, S+,
Security+, Project+, ITIL
msexchangetips.blogspot.com


ow
en

007
er

19-Mar-08 12:02 PM

The rollup is scheduled to be installed this weekend, but this specific issue
was not listed as one of the fixes. There was a somewhat generic attachment
issue listed, but the description didn't inspire confidence.

19-Mar-08 12:49 PM

I'd suspect the problem is outlook attachment security.  The key is "They
can see the attachments in OWA, or if they
choose Save Attachments from the File menu in Outlook"  which indicates
Level 2 attachment blocking.  That the files are accessable in OWA, sounds
to me that they are not being blocked at the server but rather at the
client.

Generally, when you see problems with an extention that is not on the level
1 or level 2 lists, it's because of the way the attachment is mime encoded.
Instead of application/pdf, it may be encoded application/octet-stream.

19-Mar-08 02:49 PM

Hi Terence,

While the transport rule you described fixed this particular problem, it
also broke users' ability to send normal PDF attachments from Outlook. If one
user attached a PDF to a message and sent it to another user, the recipient
received a blank message - no PDF was attached. Because of this, I had to
disable the transport rule.

To answer your other questions:
(1) Sending mail with PDF attachment from a normal Exchange mailbox via
Outlook works as expected.
(2) No, it seems to only affect certain Exchange 2007 mailboxes
(3) Unknown at this time
(4) Forwarding the message, even back to the same mailbox, causes the
attachment to become visible.

Any chance that the SP1 hotfix rollup 1 package addresses this problem?

Thanks,
Mike

19-Mar-08 02:53 PM

That's the first thing I thought of when the problem was reported, but the
only thing that changed was that the mailbox was moved from Exchange 2003 to
Exchange 2007. The Outlook client never changed, no policies or GPOs were
changed, nothing that would have caused Outlook to suddenly start blocking
PDF files. Plus, if Outlook were truly blocking the files, the users wouldn't
be able to save them from the File menu.

20-Mar-08 04:40 AM

Hello Mike,

Thank you for your update.

You can try to apply the rollup 1 of Exchange 2007 sp1. It is not hurt for
your Exchange. However, I am not sure it will fix this issue.

Based on my research, this issue is cause by the difference in Content Type
of the email sent from your Cognos.

Good e-mail had Content Type: Content-Type: multipart/mixed
Problematic e-mail has improper content type, like: Content-Type:
multipart/related

The Exchange 2007 not compatible with the Content Type. If the Content Type
of the email does not properly, the attachment will not view in Outlook. I
suggest you change the transport rule a little to bypass the internal PDF
mails.

When you create the transport rule, at the "Exceptions" page, do not simply
click next, but select "except when the message is from users inside or
outside the organization", then, click next.

Then, test this issue.

If the issue persists, you may need to connect the Cognos support. They may
have option to change the Content Type to: multipart/mixed.

I hope these steps will give you some help.

Thanks and have a nice day!

Best regards,

Terence Liu(MSFT)

Microsoft CSS Online Newsgroup Support

Get Secure! - www.microsoft.com/security

This posting is provided "AS IS" with no warranties, and confers no rights.

--------------------
one
recipient
PDF
hesitate
can
and
client?
does
rights.
moving
users
message
they
would
Exchange
workaround,

20-Mar-08 06:54 PM

How does the BI application send? Is it logging onto Exchange?  You may need
to add a MIME mapping.

22-Mar-08 02:57 AM

Hi Terence,

I've got a working solution now. The Cognos mailer writes an "X-Mailer"
header with the "Cognos" name in it, so I modified the transport rule to look
for that string in the header, plus the PDF attachment check, so now it only
rewrites the Content-Type header for those messages, and leaves all the other
PDFs alone.

Thanks,
Mike

23-Mar-08 11:55 PM

Hello Mike,

Thank you very much for sharing your resolution. I appreciate your time on
this issue.

I'm glad to hear that things are working correctly for you now. Please do
not hesitate to post in SBS newsgroup if you need any assistance in the
future. I look forward to working with you again.

Thank you and have a nice day,

Best regards,

Terence Liu(MSFT)

Microsoft CSS Online Newsgroup Support

Get Secure! - www.microsoft.com/security

This posting is provided "AS IS" with no warranties, and confers no rights.

--------------------
look
only
other
for
Type
Type
Outlook. I
PDF
simply
may
rights.
it
Outlook. If
had to
via
problem?
the
if we
the
OK,
please
mailbox
mailbox,
After
these
if

18-Sep-08 09:28 AM

Hi Terence,
Do you know if Microsoft will release a hotfix to fix this issue?  Thanks.

16-Dec-08 09:43 AM

Hello,

I've got a similar issue with hidden attachments in Outlook.  I also run Exchange 2007 and a variety of 2003 and 2007 Outlook clients.  We've got an external Fax to Email service that emails our users with messages that are to contain .tif attachments.  These attachments are visible in OWA, they are now, however visible in Outlook.  I've attempted to create a couple different transport rules, one that changed the content type to multipart/mixed and the other that changed the content disposition to attachment. Neither appears to work.  Any help would be much appreciated.

21-Sep-09 02:08 PM

Hello,
I have got similar issue, but not with PDF only. I have got this issue with XLS too, and with more than one senders.

I would like to know, if I can change the option "Content-Type" in all messages that I receive?

* From: "multipart/related"
* To: "multipart/mixed"

Can I do it, or not? why?
If no, what could I do in this case?

Thank you very much
Rog?rio




Posted as a reply to:

RE: Exchange 2007 hidden attachments

Hello Mike,

Thank you very much for sharing your resolution. I appreciate your time on
this issue.

I am glad to hear that things are working correctly for you now. Please do
not hesitate to post in SBS newsgroup if you need any assistance in the
future. I look forward to working with you again.

Thank you and have a nice day,

Best regards,

Terence Liu(MSFT)

Microsoft CSS Online Newsgroup Support

Get Secure! - www.microsoft.com/security

This posting is provided "AS IS" with no warranties, and confers no rights.

--------------------
look
only
other
for
Type
Type
Outlook. I
PDF
simply
may
rights.
it
Outlook. If
had to
via
problem?
the
if we
the
OK,
please
mailbox
mailbox,
After
these
if

EggHeadCafe - Software Developer Portal of Choice
WCF Workflow Services Using External Data Exchange
http://www.eggheadcafe.com/tutorials/aspnet/3d49fa0d-a120-4977-842a-6dafb17b6d74/wcf-workflow-services-usi.aspx