SBS 2008 doesn't receives some email

[guest]

I have a SBS2008 full updated (rollup 5 on exchange). mx record is pointed to SBS2008.
When I check it with https://www.testexchangeconnectivity.com/ there are no errors at all.
When I send mail from gmail it works.
From my domain it doesn't work and a few others domains, i get a error #4.4.7. The message could not be delivered within the specified time limit.
I disabled (after it was discoverd) SPAM setting (all) in exchange.
Does anyone can help me (with this info) with this strange problem.

[guest]

From your problem description, I understand that users in a few domains sent mails to a SBS 2008 server and got error “4.4.7. The message could not be delivered within the specified time limit.” But some domain works fine. If my understanding is not correct, please feel free to let me know.

Based on my experience, the error means the messages cannot send to that SBS 2008 server and get stuck in local Queue until it expired, and then NDR is received by sender. For such error, there are many possible causes of this issue. To narrow down the root cause of this issue:

1. Please make sure the network connectivity is fine between sender mail server and recipient mail server. It might be causing of this issue if the internet get jam between each other, and the message sent fail.

2. Please note if the Anti-Spam feature is used to Exchange 2007, if so please disable Sender Reputation function, it will do DNS reverse lookup for sender domain, if Exchange cannot detect any PRT record against sender domain on public DNS, this message will be blocked. Please check it as screenshot below and disable it:

3. Make sure there is no any Anti-Spam software and Firewall software that is installed on SBS 2008.

[guest]

1 there are no problems with the network connectivity.
2 sender reputation is disabled (all are disabled).
3 There is GFI mailessentials installed on server but I don't think this is the problem (have to disable it later on for testing).

the strange thing is that when I send my mail trough the smtp of my provider (changed on my SBS2003 from direct to smtp) it arrives at the customer with no problem.
Can you make something up with this change of my server?

Is it something on my side?

[guest]

It was a VPN LAN-LAN to the client, that was the problem.
I unabled the VPN and it works.
Thanks for your answers.