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How to allow email in which the "To:" header contains the string "Undisclosed-recipients:;" ?

I want to edit M4 File of Sendmail for allowing Undisclosed recipents. Kindly guide the sequence. My current configuration on Sendmail is as follows :

dnl Reject messages that use unqualified names in the From/To header lines

HFrom:    $>LocalCheckUnqualifiedAddr

HTo:    $>LocalCheckUnqualifiedAddr


R$* % $*    $#error $: 553 percent hack not allowed.

R$* undisclosed-recipients:; $*    $@ OK

R$* : $*    $#error $: 553 source routing not allowed.

R$+ @ $+    $@ OK

R$* postmaster $*    $@ OK

R$* `MAILER-DAEMON' $*    $@ OK

R$* Undisclosed $*    $@ OK

R$* Admin $*    $@ OK

R$+        $#error $: 553 Unqualified address: $1


dnl Reject messages that use source routed addresses

R$* % $*    $#error $@ 5.1.2 $: "553 percent hack not allowed."

R$* :include: $*    $@ OK

R$* undisclosed-recipients:; $*    $@ OK

R$* : $*    $#error $@ 5.1.2 $: "553 source routing not allowed."

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Re: How to allow email in which the "To:" header contains the string "Undisclosed-recipients:;" ?

Go to

Enter KB62827 into the "Ask a question" field and you should get back the KB article which explains how to do this.

Understand that the Firewall is blocking this for a reason and if you choose to remove this check it will no longer control messages which do not correctly conform to this aspect of the RFC.


on 28/02/12 11:16:53 GMT
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