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Message blocked due to "unacceptable attachments"
Message blocked due to "unacceptable attachments"
- Hi, I'm running Exchange 2007 with Edge Services and Forefront for Exchange. Generally, it works great! But I recently had one problem which I just can't seem to figure out.
One of our systems sends out automated reports as .XLSX files. However, the messages are always blocked at the Edge servers with the error "550 5.7.1 Message rejected due to unacceptable attachments". I have a copy of the file, and it seems fine to me. It passes virus scan, opens with Excel, and generally just... well... works.
Why would a run-of-the-mill .XLSX file be causing this behavior, and more importantly, what can I do to further diagnose and/or fix the problem?
Thanks,
- Jim
Answers
- Hi,
Did you mean the other XLSX files could be got through fine except for the automated report (XLSX files) which come from the system? And you mentioned that the .XLSX file is actually a renamed ZIP file, did you mean the .XLSX file contain the ZIP file? If it is, that should be the known issue. Please understand that the default Attachment Filter agent that is included with Exchange Server 2007 detects file types even if they have been renamed.
Now please refer to the below KB to install the corresponding update:
http://support.microsoft.com/kb/945046
Thanks
Allen- Marked As Answer byJim Mulvey Tuesday, November 03, 2009 10:23 PM
All Replies
- Hi Jim,
What happens if you run Get-AttachmentFilterEntry |FL ?
I also notice you have ForeFront installed which can block file types even with extension renaming.
Your problem isn't that there is a virus in the file - it's just a known file type to block. Check out 'Attachment Filtering" for Exchange 2007 on TechNet:
http://technet.microsoft.com/en-us/library/bb124399.aspx
Hope this helps, you should be able to modify your filter list with the above information, or continue to block and introduce a workaround.
Take care,
Oliver - Hi Oliver,
My Get-AttachmentFilterEntry is set as shown below. What's interesting is that there are no blocks for XLSX files, and other XLSX files seem to go through fine. I'm wondering if it has something to do with the fact that .XLSX is actually a renamed .ZIP file... but it's just my intuition talking, not any hard empirical data.
Still stumped,
- Jim
Type Name Identity ---- ---- -------- ContentType application/x-msdownload ContentType:applicatio... ContentType message/partial ContentType:message/pa... ContentType text/scriptlet ContentType:text/scrip... ContentType application/prg ContentType:applicatio... ContentType application/msaccess ContentType:applicatio... ContentType text/javascript ContentType:text/javas... ContentType application/x-javascript ContentType:applicatio... ContentType application/javascript ContentType:applicatio... ContentType x-internet-signup ContentType:x-internet... ContentType application/hta ContentType:applicatio... FileName *.xnk FileName:*.xnk FileName *.wsh FileName:*.wsh FileName *.wsf FileName:*.wsf FileName *.wsc FileName:*.wsc FileName *.vbs FileName:*.vbs FileName *.vbe FileName:*.vbe FileName *.vb FileName:*.vb FileName *.url FileName:*.url FileName *.shs FileName:*.shs FileName *.shb FileName:*.shb FileName *.sct FileName:*.sct FileName *.scr FileName:*.scr FileName *.scf FileName:*.scf FileName *.reg FileName:*.reg FileName *.prg FileName:*.prg FileName *.prf FileName:*.prf FileName *.pif FileName:*.pif FileName *.pcd FileName:*.pcd FileName *.ops FileName:*.ops FileName *.mst FileName:*.mst FileName *.msp FileName:*.msp FileName *.msi FileName:*.msi FileName *.psc2 FileName:*.psc2 FileName *.psc1 FileName:*.psc1 FileName *.ps2xml FileName:*.ps2xml FileName *.ps2 FileName:*.ps2 FileName *.ps11xml FileName:*.ps11xml FileName *.ps11 FileName:*.ps11 FileName *.ps1xml FileName:*.ps1xml FileName *.ps1 FileName:*.ps1 FileName *.msc FileName:*.msc FileName *.mdz FileName:*.mdz FileName *.mdw FileName:*.mdw FileName *.mdt FileName:*.mdt FileName *.mde FileName:*.mde FileName *.mdb FileName:*.mdb FileName *.mda FileName:*.mda FileName *.lnk FileName:*.lnk FileName *.ksh FileName:*.ksh FileName *.jse FileName:*.jse FileName *.js FileName:*.js FileName *.isp FileName:*.isp FileName *.ins FileName:*.ins FileName *.inf FileName:*.inf FileName *.hta FileName:*.hta FileName *.hlp FileName:*.hlp FileName *.fxp FileName:*.fxp FileName *.exe FileName:*.exe FileName *.csh FileName:*.csh FileName *.crt FileName:*.crt FileName *.cpl FileName:*.cpl FileName *.com FileName:*.com FileName *.cmd FileName:*.cmd FileName *.chm FileName:*.chm FileName *.bat FileName:*.bat FileName *.bas FileName:*.bas FileName *.asx FileName:*.asx FileName *.app FileName:*.app FileName *.adp FileName:*.adp FileName *.ade FileName:*.ade - Hi,
Did you mean the other XLSX files could be got through fine except for the automated report (XLSX files) which come from the system? And you mentioned that the .XLSX file is actually a renamed ZIP file, did you mean the .XLSX file contain the ZIP file? If it is, that should be the known issue. Please understand that the default Attachment Filter agent that is included with Exchange Server 2007 detects file types even if they have been renamed.
Now please refer to the below KB to install the corresponding update:
http://support.microsoft.com/kb/945046
Thanks
Allen- Marked As Answer byJim Mulvey Tuesday, November 03, 2009 10:23 PM
Hi,
Any update on this issue?
Thanks
Allen
- Hi Allen,
Sorry, I was delayed with other non-Exchange issues. I've tried the suggestion in KB945046, and it WORKED! Thank you.
The article is really quite sparse on what, exactly, I'm doing to the server though. Maybe I had a little too much Halloween spirit but a key named "AllowInvalidAttachment" sounds a little spooky. Other than my perfectly valid Excel document, what other documents or characteristics make an attachment "Invalid".
Thanks again,
- Jim - Hi,
Glad to hear that is the useful.
Thanks
Allen - Hi Allen,
We are also facing the similar issue but the file type is csv.
<<< 550 5.7.1 Message rejected due to unacceptable attachments
554 5.0.0 Service unavailable
We have roll up9 in our environment, If I add <add key="AllowInvalidAttachment" value="true" /> in EdgeTransport.exe.config file... will the issue going to resolve. Please confirm.
Thanks im advance,
Toufiq.
