Which Port is the safest for the inbox?

I have an imap.arcor.de e-mail account. Is it safer that I under “IMAP” port 143 (SSL / TLS enforce) to set? Or is it safer that I set port 993 (SSL / TLS on certain port (legacy))? On the homepage of Arcor.de it is written that port 143 uses TLS encryption and port 993 uses SSL encryption.
What kind of port should I now set in the eM client under “IMAP”? Which port is the safest? Port 993 or port 143?

Hi Jens,

Tbe higher port numbers 995 for POP and 993 for IMAP represent the secure ports
https://www.arcor.de/portal/page/static/help/email

Port 143 is now seldom used - if not at all -for mail

Peter

Hi Peter,

So, would you recommend port 993 to me? But then I have to set “Use SSL / TLS on specific port (legacy)” for the port to work. Is that right?

But why, when I set up my e-mail account at the beginning, does the eM Client program automatically set me to port 143. With the security policy: Force SSL / TLS?

eM Client usually sets the safest method in the beginning, right? With the security policy: Force SSL / TLS?

But according to you, the port 993 is the safest. Funny.

Greetings, Jens

Hi Jens,

Thanks for the feedback.

“So, would you recommend port 993 to me? But then I have to set “Use SSL / TLS on specific port (legacy)” for the port to work. Is that right?”

Yes, yes and yes… That’s the setting under the IMAP tab. 
for incoming mail

"But why, when I set up my e-mail account at the beginning, does the eM Client program automatically set me to port 143. With the security policy: Force SSL / TLS?

"Good question. This recently happened to me without doing anything and to an established account Hotmail or Outlook.com.
It all of a sudden failed to either download or send mail.

Checking the ports under the repective tabs - IMAP and SMTP revealed the change.
For IMAP I had to change it  (back) to port  993 and Use SSL / TLS on specific port (legacy)
For  SMPT (sending) I had to use  Force SSL/TLS and port 587 - or 465

“eM Client usually sets the safest method in the beginning, right? With the security policy: Force SSL / TLS?”

As you can see - not necessarily.

“But according to you, the port 993 is the safest. Funny.”

This is not my opinion, but rather a fact.
The higher port numbers are the more secure ones.
It also says so in the description : “verschlüsselt” 

Hope you get it working - it should ,barring other interference.

Peter

So there is now with me: SSL / TLS on certain port use (Legacy). But why is Legacy in parentheses? Legacy means outdated, right?

“Legacy means outdated, right?”  or older…

Yes, to my understanding as well,_ _but it’s the only way I get it to work.
Then again - you’re using a secure and newer port 993.
so it’s a puzzle for me as well…

If it works , keep it that way ,unless we get info to the contrary from eM Client staff.

Hi Jens,
both options are safe, SSL and TLS are two cryptographic protocols used for communication between servers and applications.
SSL is the predecessor to TLS, that is why the SSL on port 993 is called the (Legacy) option, in this case really just meaning the ‘older’ option - definitely not an obsolete one, it’s still secure and some servers have it as the preferred option.

The port number itself does not dictate the security level - it depends on what protocols the server and the client app support for that port number.
Since your provider - Arcor.de - has TLS encryption enabled on port 143, then this connection is protected by the newer protocol TLS on that port. Other mail servers might not support TLS at all and might have SSL on 993 instead and have the ‘unsecured’ connection on 143.

The account setting eM Client assigns during the ‘Automatic setup’ are actually taken from your mail server’s autodiscover settings - ie. these settings are the recommended ones on your mail server.

Regards,
Olivia