Hey,
In the few cases we had regarding this the problem only occured when the mail was coming from PHP with postfix. We solved this by modifying the php.ini files sendmail path.
Basically in the php.ini file you will have something like:
sendmail_path = /usr/sbin/sendmail -t -i
Try commenting this line out (put a ; before it) and add the following line:
sendmail_path = "sed 's/\r$//' | /usr/sbin/sendmail -t -i"
You might have luck. Make sure the path is correct (/usr/sbin/sendmail is default) or the same as the one you commented out. After this is modified restart the apache service and try testing. I have not seen any tickets yet that this didn't solve for us. If it doesnt work or it breaks things comment out the new line and uncomment the old line and restart apache again.
-Ray C.
Raymond Corbin | Support Analyst | HostMySite.com | 877.215.4678
rcorbin@hostmysite.com
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