Avast 4.6.652 Email Problem

[hgratt]

I have an IBM R40 Thinkpad with win xp pro, sp2 and all latest patches. I also use Zone Alarm Free 4.xx (no privacy stuff, etc).

I use Comcast cable modem as a provider.

I have just now noticed that when I send emails, my upload speed is about a 1/3 of what it should be. If I disable outbound scanning, upload speeds are near normal.

What is going on and how do I fix it so it works with outbound scanning enabled?

Thanks,
Harvey

[lukor]

What do you mean by upload speed?

[hgratt]

I use Netpersec to monitor my download and upload speeds. When I send a large file (several MBytes), I see around 30 Kbytes/sec speed in uploading the file to the designated email address. If I disable outbound scanning, I see about 90-92Kbytes/sec sending speeds.

Harvey

[lukor]

I use Netpersec to monitor my download and upload speeds. When I send a large file (several MBytes), I see around 30 Kbytes/sec speed in uploading the file to the designated email address. If I disable outbound scanning, I see about 90-92Kbytes/sec sending speeds.

Harvey

Hmm, by speed one usually mean transferring certain amount of stuff (let's say pieces of eight) in certain amount of time (let's say seconds). If your download speed lowers to 1/3, does it also takes 3 times longer to send an email of the same size?


Don't understand me wrongly; since I know how outbound scan works I can easily imagine that speed measuring software does not measure correctly.

[hgratt]

I use Netpersec to monitor my download and upload speeds. When I send a large file (several MBytes), I see around 30 Kbytes/sec speed in uploading the file to the designated email address. If I disable outbound scanning, I see about 90-92Kbytes/sec sending speeds.

Harvey

Hmm, by speed one usually mean transferring certain amount of stuff (let's say pieces of eight) in certain amount of time (let's say seconds). If your download speed lowers to 1/3, does it also takes 3 times longer to send an email of the same size?

Yes, one can see the significant slowdown in the upload file transfer.

Harvey

[lukor]

With outbound mail scanning you are uploading the mail twice - firstly it's uploaded and cached in the internet mail provider, then it is analyzed, attachments unpacked, scanned for viruses and then it is continuing its way to the destination server.
From the mail client perspective it goes very quickly, than it stops for a while transferring 0 bytes/s, then again it goes very quickly (for the next email). That is why the speed measurement might get confused.

This process and the upload (even to localhost mail scanner) takes some time and may be visible when network speed are very high - but I would not expect a significant slowdown with speeds about 90 Kbytes/s. We can re-check it in the morning and see if we see such a slowdown.

Of course, sending large compressed file has its own overhead. The attachment needs to be uncompressed before scanning and for large files it really does take some time.

[hgratt]

FWIW, I have just swithced to Avast from Norton NAV 2004. NAV would scan the file for a few seconds,and then send it off at about 92KBytes/sec to the mail server.

Avast does seem to be noticibly slower overall as well as showing slower transfer speeds. I assume that Avast has also scans the file completely before sending it off. If so, I would expect speeds to the mail server in the 90-92 KBS range.

Thanks,
Harvey

[alanrf]

When I first saw this post I assumed that this was just a perception issue and  that the numbers could be explained by the "double send" that Lukas has explained above. 

I am also a Comcast cable user so I thought I would put it to the test.

I sent the same message 4 times. Each message was sent to the same address through my Comcast smtp server.  The message contained one word of text and a single ~2.5Meg pdf file attachment.   

The only measurement I used was the elapsed time from clicking the send to receiving the "mail successfully sent" message in my mail client. 

Message 1  without Avast scanning   90 seconds
Message 2       with Avast scanning 137 seconds
Message 3       with Avast scanning 138 seconds
Message 4  without Avast scanning   90 seconds

So about 50% longer to send the same file with Avast scanning active for my system and Comcast connection, but nowhere near the decrease reported by hgratt.

I must assume that hgratt has a non-standard Comcast cable connection.  Mine is 4Mbps/384Kbps.  With my non-Avast scan I am uploading at about 30Kbytes/sec.  You would have to have a significantly faster upload connection to be sending mail at 90-92Kbytes/sec (either that or Netpersec is giving misleading information).

[MFB]

FWIW, I have just swithced to Avast from Norton NAV 2004. NAV would scan the file for a few seconds,and then send it off at about 92KBytes/sec to the mail server.

Avast does seem to be noticibly slower overall as well as showing slower transfer speeds. I assume that Avast has also scans the file completely before sending it off. If so, I would expect speeds to the mail server in the 90-92 KBS range.

Thanks,
Harvey

You just switch from Norton?  Make sure you check and remove every single thing with Norton or symantec in it's name.  If I recall, after you unistall Norton, Symantec live update still remains in your computer. 

[hgratt]

When I first saw this post I assumed that this was just a perception issue and  that the numbers could be explained by the "double send" that Lukas has explained above. 

I am also a Comcast cable user so I thought I would put it to the test.

I sent the same message 4 times. Each message was sent to the same address through my Comcast smtp server.  The message contained one word of text and a single ~2.5Meg pdf file attachment.   

The only measurement I used was the elapsed time from clicking the send to receiving the "mail successfully sent" message in my mail client. 

Message 1       with Avast scanning   90 seconds
Message 2  without Avast scanning 137 seconds
Message 3  without Avast scanning 138 seconds
Message 4       with Avast scanning   90 seconds

So about 50% longer to send the same file with Avast scanning active for my system and Comcast connection, but nowhere near the decrease reported by hgratt.

I must assume that hgratt has a non-standard Comcast cable connection.  Mine is 4Mbps/384Kbps.  With my non-Avast scan I am uploading at about 30Kbytes/sec.  You would have to have a significantly faster upload connection to be sending mail at 90-92Kbytes/sec (either that or Netpersec is giving misleading information).

I have the so-called gold speeds - 6mbps/768kbps. As I indicated, I get about 30-34 KBS with outbound scanning active and about 90 KBS with outbound scanning disabled.

If you use the "stop watch test", then I can see where the time spent in scanning the file would change the overall speeds. I think in your case, 384kbs should be about 48 KBS. FWIW, when I had the 4/384 package my upload speeds would be about 46 KBS. I have also verified these upload speeds on various speed test sites.

BTW, should the "with and without" messages be reversed? I assume the longer times correspond to the outbound scanning active case.

Thanks,
Harvey

[hgratt]

FWIW, I have just swithced to Avast from Norton NAV 2004. NAV would scan the file for a few seconds,and then send it off at about 92KBytes/sec to the mail server.

Avast does seem to be noticibly slower overall as well as showing slower transfer speeds. I assume that Avast has also scans the file completely before sending it off. If so, I would expect speeds to the mail server in the 90-92 KBS range.

Thanks,
Harvey

You just switch from Norton?  Make sure you check and remove every single thing with Norton or symantec in it's name.  If I recall, after you unistall Norton, Symantec live update still remains in your computer. 

Yeah, I was careful. I used add/remove and then made sure to hunt down all the symantec folders and manually remove them.

Thanks,
Harvey

[alanrf]

hgratt,

thanks for spotting the error in my timing report.  I have edited it.

A thought that just occurred to me - I have not checked the effect yet.  I have the same ZoneAlarm firewall as you - do you have the message scan disabled in ZoneAlarm?

[hgratt]

hgratt,

thanks for spotting the error in my timing report.  I have edited it.

A thought that just occurred to me - I have not checked the effect yet.  I have the same ZoneAlarm firewall as you - do you have the message scan disabled in ZoneAlarm?

I had the basic message scan enabled, but it's only for incoming mail. I tried turning it off and it made no difference. Also, shutdown ZAF, but again minimal difference.

Right now, I'm not getting good speeds even with outbound scanning turned off - but better than with it turned on. I may try uninstalling Avast and see what happens.

Harvey

[alanrf]

Rather than uninstalling Avast try this:

On the Internet Mail Scanner:

Customize > Redirect tab

Change the SMTP port to a something like 15025

Select OK

Terminate and restart the Internet Mail Scanner.

Now try your test.

I've just being doing some scanning - I'll write it up in another post.

[hgratt]

Uninstalling Avast made no difference. Still getting not quite so good speeds - I guess a Comcast problem for now. FWIW, I also tried AVG and could not get it to function with my email at all.

Anyway, the problem still persists, I need to disable outbound scanning in order to get acceptable upload speeds.

Harvey