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How to configure Exchange Server

We are asked frequently how the Exchange Server should be configured to work with POPcon. These guides list the actions necessary to configure your Exchange server in a standard way so it works well with POPcon and the Internet.

Exchange Configuration guides

Step by step guides with many screenshots.


FAQ - frequently asked questions

See these frequently asked questions and answers for fast hints:

POPcon and POPcon PRO frequently asked questions:

How can I transfer my POPcon configuration settings to my new server without retyping it all?

"530 5.7.1 Client was not authenticated" Error message from Exchange

My Exchange 2007 or 2010 does not accept emails larger than 10MB. What can I do?

"452 4.3.1 Insufficient system resources" error message from Exchange

"550 5.7.1 Unable to relay" error message from Exchange

There are .msg files in the POPcon folder with undistributed emails left after we solved an Exchange problem. How can we redistribute them?

Exchange 2013 SMTP error "451 4.7.0 Temporary server error. Please try again later. PRX"

Emails to recipients that are unknown in my Exchange/ActiveDirectory organization are rejected by my Exchange Server and seem to remain in POPcon's queue.

Does POPcon work with Exchange 2010? 2007? 2003? 2000?  5.5? SBS versions?

The distribution of incoming emails from a mailing list does not work correctly. What can I do?

What do I do if all emails get forwarded to the postmaster because they "do not have local recipients"?

POPcon hangs when my virus scanner deletes infected *.msg files from the POPcon folder!

Can I start the mail retrieval cycle from the command line (.bat, etc.) ?

Why is email to unknown recipients in my domain not forwarded to the postmaster?

POPcon downloads email ok, but can't reach my exchange server - what can I do?

BCC recipients do not receive the email, although recipients listed under TO: and CC: do. Any hints?

How can I get POPcon to not work with my ISA-Server (proxy) ?

What can I do about the error message "Host did not acknowledge DATA command [554. 5.5.2 No valid recipients]"?

POPconAdmin does not work or has problems communicating with my POPcon service?

Will I lose emails if my Exchange Server happens to be down when POPcon tries to send emails there?

Is there a trace of POPcon's actions somewhere so we can check where email messages came from and where they went?

How can I get rid of downloaded emails that are stuck in POPcon's queue?

All emails are suddenly tagged as SPAM after a period of no problems with the antispam feature!

POPcon does not install on my machine. What can I do?

Exchange/SMTP connection was unexpectedly closed or error message "454.5.7.3 Client does not have permission to submit mail to this server."

How can I resend already downloaded messages?

How do I configure Exchange and POPcon if I want to handle only part of a domain?

How can I diagnose malfunctioning antispam blacklist server lookups?

What could be the reason for ''Mail transfer to exchange failed, reason: Connection to host denied'' ?

Exchange does not accept some email from POPcon and keeps saying "550 5.7.1 Requested action not taken: message refused"!

POPcon always forwards my email to TWO Exchange mailboxes: The real recipient and a recipient named like my catch-all mailbox at the ISP. How do I stop that?

POPcon says that it drops copies of downloaded email - what causes this message?

What can I do when exchange does not accept some emails and comes up with an error message: "550.5.5.1 user unknown" or "503.5.5.2 need Rcpt command" ?

The new version 3.20 of POPcon can download IMAP email. Can it download email from AOL accounts with this?

Can I use POPcon to download email from Gmail accounts?

"Out of Office" messages are returned to internal users but not external users on the internet. Is this a problem of POPcon?

Why does POPcon need to know the "accepted domains" on the POP3/IMAP config tab?

How can I enable non-delivery reports (NDRs) to external mail senders in Exchange 2003?

Mail does not reach mail-enabled public folders. What could be the reason?

Does POPcon also work with Lotus Domino Server?

Only messages less than 10MB in size seem to come through, does POPcon impose a size limit?

Windows Data Execution Prevention is stopping or crashing the POPcon antivirus engine. What can I do?

Exchange does not accept any email from POPcon. Error message: "530 5.7.0 Must  issue a STARTTLS command first"

Why is the spam checking taking so long? It takes 30 seconds for a single message!

What does the error message "[blacklist] could not be tested and will not be used" mean?

Mails to mail-enabled public folders end up as posts instead of as emails. Can that be changed?

How does the POPcon PRO antispam feature work / why is it not 100% accurate?

What is the shortest mail download interval supported by POPcon

POPcon moved emails in the TOOLARGE or BADMAIL folders. How can I resend them to Exchange?

What does a "421 4.4.1 Connection timed out" Exchange 2007 SMTP error message mean?

My Exchange 2007 only accepts one or a few messages at a time from POPcon. How can I increase the number?

Error message "Exchange aborted receiving the message after 2xxxx bytes." - what to do?

Why doesn’t my new distribution group accept emails from outside?

I want POPcon to forward some accounts to a non-local mailbox on the internet but that does not work. How can I do this?

"552 5.3.4. Header size execeeds fixed maximum size" error message from Exchange

How can I have non-delivery reports (NDRs) sent for unknown users?

"421 4.4.2 Message submission rate for this client has exceeded the configured limit" error message from Exchange

I need to have non-delivery reports (NDRs) sent for emails that are too large instead of moving them into the TOOLARGE folder

Mail transfer to Exchange failed, reason: Could not reach Exchange SMTP server - check IP port 25 is not blocked

"530 SMTP authentication is required" what does it mean?

IONOS blocks non-delivery reports and out-of-office messages

CSCatchAll frequently asked questions:

How do I configure CSCatchAll? The Administrator utility only allows me to enter a license code.

I installed CSCatchAll and configured a catch-all account but it does not seem to work at all! What can I check?

ChangeSender frequently asked questions:

ChangeSender installed correctly but the sender address appears unchanged

How can I restrict my users choices for the Send-As address?

How can I use the same sender address for two Exchange mailboxes?

How can I disable the Add-in for all users by default?

MultiSendcon frequently asked questions:

504 5.7.4 Unrecognized authentication type - error when using Office 365 smtp relay

IONOS blocks non-delivery reports and out-of-office messages

BotFence frequently asked questions:

How to protect Wordpress sites with BotFence

Full text of all FAQ articles in one compact HTML file: Knowledge Base

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