Skipping Check of MIME Part 0 - ORF Forums

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I keep getting this message in my logs > Skipping check of MIME part 0: the part was too large for content-based tests. Decoding was skipped to prevent performance issues. < I have no external agents and this is a clean install. Using Exchange 2016.

Thinking maybe something was corrupt, I uninstalled, removed the folder and reinstalled, but error persists.

by AJ 1 year ago

Hello AJ,

The error message indicates that the mail content was too large to be tested. In most cases, this is caused by malformed emails, when the attachment is submitted as part of the mail body. Since testing such an email could bring ORF - and you server - to a halt (as it would have to check an excessive amount of text against regexes/wildcards), content checking is skipped to avoid any problems. I am afraid there is nothing you could do in ORF to resolve this, as the problem is with the email itself - which was passed to ORF by the SMTP/Exchange server already malformed.

by Daniel Novak (Vamsoft) 1 year ago

@Daniel Novak (Vamsoft): So what do I do? This is causing ORF to be useless as nearly every message is telling me this so my users are getting slammed by spam. Seems like a pretty easy job for the spam senders to get around the filter.

by AJ 1 year ago
(in reply to this post)


@AJ: Are those emails actually delivered to the recipients though - or dropped by Exchange? If practically every email that ORF checks seems to be malformed, that indicates an issue with the underlying system and/or with the registration of windows components that ORF relies on. Try re-registering the CDOSYS component - which ORF uses to parse emails - to see if that solves the issue.

1. Start the windows command prompt with elevated rights

2. Run the following command (you may have to change the path to c:\windows\syswow64\cdosys.dll - verify the location of the .dll beforehand):

regsvr32 C:\Windows\System32\cdosys.dll

If the above does not help, unregister the cdosys.dll first:

regsvr32 /u C:\Windows\System32\cdosys.dll

Then re-register cdosys:

regsvr32 C:\Windows\System32\cdosys.dll

Please, let me know if this has helped.

by Daniel Novak (Vamsoft) 1 year ago
(in reply to this post)

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