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How to recover mailbox for cyrus-imap?

From the guide, we know that cyrus saves emails in mailboxes under /var/spool/imap/. But deleting mailbox is not equal to deleting the folders and files in /var/spool/imap/. If you just remove the directories under /var/spool/imap/, you will get the error

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Create mailbox for cyrus-imap

If you follow my guide on postfix/cyrus-imapd set up, you may encounter a problem when login the mail server to retrieve emails. starttls: TLSv1 with cipher RC4-MD5 (112/128 bits reused) no authentication badlogin: . [xx.xx.xx.xx] plaintext admin SASL(-13): user not

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How to configure postfix not to send deferred emails repeatedly

For webmasters in the real world, the delivery retry function of postfix is troublesome sometimes. If you have a cron job generating emails all day and all night, and some recipients are unreachable or postfix service stops accidentally, many emails

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cyrus-master does not listen on ipv4 port

I met a strange problem: cyrus-imapd service stopped for unknown reason and I could not receive emails. Even I restarted the service: service cyrus-imapd start I still could not receive emails. Telneting to the mail server showed the port was

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will iptables block connections from local host?

If you insert the following rules in iptables, iptables -A INPUT -p tcp –dport 1234 -j DROP The firewall will block the connections to the port 1234 from remote computers. I wonder if iptables can also block the connections from

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enable ssl for postfix in sentora

Like dovecot, sentora does not enable ssl for postfix by default, either. How do you know if ssl is enabled? You can use the command “netstat -antp|grep master”. master is the daemon of postfix. You’ll see postfix uses the port

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How to enable SSL for Dovecot in Sentora?

As always, Sentora does not care about security and SSL stuff for its users. So by default, dovecot provided by Sentora listens on port 110(POP) and port 143(IMAP) and the communication thru the ports is not encrypted. We have learned

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difference bewteen memcache and memcached

The daemon(server) of the memcache system is called memcached. You can install the memcache server using “yum install memcached”. There are two php memcache extensions: memcache and memcached, both can work for the same memcache server mentioned before. memcache¬† is

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fix a dns problem

Today I encountered a problem when installing python-setuptools with yum. yum install python-setuptools The above command runs for a long time then shows the following error: yum install python-setuptools Loaded plugins: fastestmirror Determining fastest mirrors Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=6&arch=x86_64&repo=os

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Helo command rejected: need fully-qualified hostname

I got this error when I tried to send an email to a local user¬† using outlook express, and as an unauthorized person. If I check the option “my server needs authentication” on, and input the correct account information that

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