We are moving from Exchange 2007 to Exchange 2013. I have noticed that people are complaining that messages are dropping into their junk mail filter after being migrated. These are messages that come from our external helpdesk software. The mail gateway forwards them to Exchange 2007 Hub servers. The users on the 2007 servers don't have a problem, just the ones who have been migrated already.

Can we push out something that always allows these messages to bypass the spam filter? Why does Exchange 2013 behave differently than 2007. I thought this was being handled by the junk mail filter in outlook and not on the exchange server itself.

Since we are dealing with two filters this question has to be answered twice, once for each of:

1)Outlook client-side junk filter
2)Exchange server-side IMF/Content Filter

1)The solution for the Outlook client side junk filter is use Group Policy.

2)Exchange 2010/2013 Mailbox Junk Email Configuration

As from Exchange 2010 this void was filled with the MailboxJunkEmailConfiguration cmdlets.

Turing on the Junk Folder for the User1 mailbox is simply a matter of entering this cmdlet at the Exchange Management Shell: 
Set-MailboxJunkEmailConfiguration -Identity User1 -Enabled $true

...to disable it: 
Set-MailboxJunkEmailConfiguration -Identity User1 -Enabled $false

And to enable it for all users in the specified Mailbox Database: 
Get-Mailbox -Database <Mailbox Database Name> | Set-MailboxJunkEmailConfiguration -Enabled $true

Of course you can also use the Get-MailboxJunkEmailConfiguration to read the current settings.

Using these cmdlets we can also manage other per mailbox anti-spam settings such as the list of blocked and trusted senders.

I hope that helps.

BTRowdy1 start by clarifying this point please:
"I thought this was being handled by the junk mail filter in outlook and not on the exchange server itself."

You need to tell us what is running on your Exchange servers. Are you running the Exchange Anti-Spam agents? If yes on which of the Exchange servers are the agents running? Just Ex 2007? Both?

Curt Winter here posted an abstract of one of my articles, here is the original:
http://www.exchangeinbox.com/article.aspx?i=155

This might be helpful, but first you need to better describe what is running at your end...

Hi ,

Thank you for your question.

In addition above suggestion, I know this issue occurred on all users by your state.

There are two other options for us to solve it:

1.        White listing
2.        Create transport rule to reduce the value of SCL: we could check the value of SCL in head information, then we could create a transport rule to modify it, there are two links for us:

https://technet.microsoft.com/en-us/library/jj200686(v=exchg.150).aspx

https://technet.microsoft.com/en-us/library/dd351127%28v=exchg.150%29.aspx

If there are any questions regarding this issue, please be free to let me know. 

Best Regard,

Jim