Hello
I have the newest version of Avast free and Win XP Prof. The problem is as follows, I have wrote a script (.exe) which should send an E-Mail over SMTP port 25, but this don’t work. It has to be avast who blocks the port, because on other PCs, which the same configuration, but no avast installation, it works very well. I have installed the real-time shield of avast nothing else. I have it deactivated, but it don’t work.
Any suggestions?
First, avast doesn’t block, but scans and alerts to infection, which presumably it isn’t doing. avast free doesn’t have a firewall so doesn’t block ports.
avast’s Mail Shield will intercept calls to port 25 so the emails can be scanned and then sent on their way. It will expect that application (.exe) to be using the SMTP Protocol standard, so if it doesn’t then it could be getting tired up, so does your little application use the SMTP Protocol ?
Are there any errors displayed, if so please give the full error ?
If you only have the File System Shield installed on your configuration, then there is no way the Mail Shield can intercept it and the file system shield wouldn’t be interested in that traffic. If you are saying the file system shield is blocking the .exe you use, again the same answer it doesn’t block but scans and alerts to infection.
So if it appears to be being blocked there is something else in the mix and that could be conflict with another security application.
Have (or did) you another Anti-Virus installed in this system, if so what was it and how did you get rid of it ?
What other security based software do you have installed, anti-spyware, firewall, etc.) ?
Yes my application does use the smtp protocol. There are no errors displayed, I don’t receiver the e-mail. The exe isnt’ blocked, only sending over smtp doesn’t work. I tested it on serval PCs, also on new virtual machines, which have only installed avast, so I think the problem could be avast. On the pc on which it works, there is no avast installed.
I did not have had installed another anti-virus software, only avast and the windows firewall, but also with deactivated windows firewall it doesn’t work.
Well, really hard to diagnose some custom made EXE to send mail. How’s it sending mail, for starters? Does it try to encrypt the traffic?
If it were an avast issue I would have expected an error message if it could send the email, normally this error may come form an email application (where an email isn’t sent, etc.) if there is a conflict between avast and the email client.
So I don’t know if your applications returns the normal email errors or not (?) making it harder to track down what the problem is.
If it doesn’t report errors, etc. then what doktornotor is hinting at is if they are being transmitted using SSL, then avast can’t scan them and that should through up an avast error (which you say it doesn’t). If there is a mis-match between the email client and avast trying to handle an SSL transmission, that would normally result in the email client giving an error.