[Exim] Retry

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Hi guys,

I'm acting as a secondary mail server for a friend of mine... In other words his secondary MX records are pointing to my mail server for support relaying.

DNS myfriend.com

MX 0 mail.myfriend.com
MX 5 mail.MYSERVER.com

A problem that I have encountered however is that is server is down quite often and now my mailserver rejects mail for his host relaying through me immediately as it reaches my server, when his server is down of course.

It rejects with a:-
retry time not reached for any host after a long failure period

Now, I have tried the suggestions on the exim site. but to no avail. does anyone have any suggestions for what I can try next?

Thanks,
Shane :)
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