centOS

What are you using for anti-spam?

this is our internal smtp gateway

I don't know much about Linux, our emails with pdf attachments are getting quarantines, I have to manually release it each time

So what are you using on your smtp gateway? Centos by itself doesn't have everything for a proper gateway. You must have some add on software doing the spam and/or anti-virus scanning.

Exactly.  What URL do you put into your browser to reach your quarantine?

Is it labeled?

Linux is not going to quarantine anything.

I generally log into my Linux box (name of my server) and open Linux log in with root and password
and release message id

I don't use any url

Where do you check your emails? It could be the anti-virus/anti-spam client on your PC mail client

CentOS by itself shouldn't have anything that does any spam filtering... Unless the PDF files make the message go over the size limits in Sendmail... But that should bounce, not hold...

But lets start over...

Did you build this smart host or was it someone else?

Do you have any docs?

someone  else , it holds until I release

Is this happening on server without accessing emails by mail clients?

I just want to release pdf files from that internal smtp , any commands please that will help

first we need to know where the emails get identified and quarantined. Do you know if anti-spam / anti-virus is configured / installed along with your mail server.

Please run below command and post output:

netstat -pat | grep smtp

Your question is almost like going to the doctor and saying " I hurt, but I can't tell you where it hurts".
We are trying to help you, but without identifying WHY the pdf files are getting held, it is almost impossible to tell you how to release them.

there is no anti spam/anti virus installed , I ran the command

one needs to go to quarantine folder and release them , can you give m ethe path

ls /alt?

we have external SMTP gateway which is stripping java script from pdf and then releasing the email which hits internal smtp gateway and gets held up there.

we then manually release those pdf files. we wants that each time it gets held up in quarantine of internal SMTP should not happen

Then your internal SMTP has some sort of filtering involved. As we said, most SMTP servers, whether linux OR windows based have filtering by default. It would be difficult to figure this out without inspecting the systems involved if you don't know what processes are involved.

how can we check filtering

The above command  netstat -pat | grep smtp  is a start. Then it will most likely lead to other questions.

everyone is seeking information that might help identify your setup.

How are you logining into the Linux box? Are you sshing? Are you using a web browser to access webmin, cpanel, or the like.
If you ssh, what commands do you run to list the quarantined messages, to release?

you have to have some settings that deal with the criteria on the basis of which emails/attachments are quarantined. Do they only quarantine the attachment or the entire email?

I am assuming you gave up or went elsewhere to get answers... Because I doubt I helped you in fixing this...

The solution may not have been the answer however the expert assisting asked all of the right questions that should have pointed the author in the correct direction.

I would leave the points as is because the assistance provided here may help someone else.

All experts asked valid questions and wanted to help. Points should be split then or a solution should be given.

I now manually release each pdf files from quarantine  , by typing command release message id,

I wanted to know if I can over come that. it is a Linux server and I log in with user name : root and password

pramod1, you seriously need a professional to look over your server, tell you what is running and the best steps to take to manage it.

pramod1, if you have root access to the server then run the command given and post the output.

I don't know which command to run, to permanently release message id from quarantine.

can you give me some Linux commands, as to how to go to ls directory or quarantine directory in Linux

can you run below command and post output so we can help?

netstat -pat | grep smtp

there lot of smtp domains listed and I can't post it

I would recommend doing a "ps awx" and send that output via a private message in EE to the expert assisting.  You can always followup here if you find something worth noting.

Are you using a WEB Based (access the management interface using a web browser)?
If you have a web based interface, you need to look at the available settings for each domain to see what the classification rules are and then see if you can exempt if you want PDF from this or if the option exist on lassification value adjust the value assigned when PDf is the attachment to lower the probability of a PDf being quarantined.........

The interface will often tell you what it is. You may need to contact those who manage/provided this to see what your options are available to streamline.

I am taking professional help who manages on site  so would like to close this question

you can choose responses that helped you, or get further information on what you should ask and expect from those with whom you are speaking.
note, whether in this forum or in face to face, you should provide as much information as you can, ambiguity will mean that it might take longer to get to the bottom of what your setup is and will likely increase the costs. The other option those with whom you are speaking will propose a completely new solution............... under the presumption that it will be more cost effective which often is likely.
the problem however, is that there does not seem to be a clear picture of what you have so a new solution might not fully replicate/replace the existing and will only be noticed down the line.

thanks Arnold  

expert on site is checking your below statement which helped

If you ssh, what commands do you run to list the quarantined messages, to release?

Again... Without knowing what is quarantining the messages we CANNOT give you the commands to release them... Mail programs do not usually quarantine on their own, it takes other programs/scripts to do this...

We are trying to help you, but asking the same question again doesn't make it easier to answer it...

My Comment, http:a#41756582 seems to have helped. But I'll let it go.

I got an expert at my site and got corrected