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F-Secure partially blocking uTorrent


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Anyone with F-Secure can you please help me unblock uTorrent.

I just purchased F-Secure and it's a very easy program to use but when downloading at my max line speed (8.86MB/s) I get hit with popups saying "A suspiciously small data fragment was detected and blocked, this could be a data fragmentation attack"

Every time this happens my downloads go from my max speed, to only 9.0KB/s and then after about 60 seconds they jump instantly back up to full speed and then I get another warning from F-Secure..

I would really like to be able to use the program without having to disable the firewall.. I did pay extra for it...

uTorrent shows that my ports are forwarded. I have allowed all Inbound and Outbound traffic to uTorrent. As well as forwarded my chosen port (6881), in both my Buffalo Infinity router, and my Firewall.

I have told F-Secure to block anything shorter than 65535 bytes. Is this ok?

Here is a screenshot:


Please someone tell me how to just allow uTorrent to do whatever it pleases without getting annoying popups every few seconds..

Could these really be fragmentation attacks? What should I set the setting to, I don't seem to be able to find an option anywhere to just turn this feature off or allow anything for just uTorrent etc.

Thanks a lot!

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Honestly, given the addresses in the entry and what's going on, it's a case of f-secure being extremely overparanoid over ipv6 teredo tunneled traffic. You need to find in f-secure's settings where to turn off the "protection" against this kind of attack since all it's protecting you from is using your internet connection properly.

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Ok I think I have set it up ok...

I set a rule:

1. Allow all traffic for

2. IPv6 Addresses on

3. Inbound or Outbound called

4. 'uTorrent Fragmentation Allow'

All messages have now changed from 'Blocked' to 'Allowed' after subsequently adding the rule.

It wasn't easy to make.. there were a lot of things I had to mess around with.

Is this going to be a security risk though... allowing ALL IPv6 addresses no matter what?

I didn't just pay extra for a firewall that now might as well be disabled :/

This AV is really good in my opinion, even if there is this small issue (which is now hopefully fixed) it was a complete snap to portforward and set up other things, this was a bit more complicated but not even half as complicated as using 'Outpost Pro Firewall' was...

Thanks for your continued help!!

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Well now it says this in the log:


But I am still getting the rare popup saying that it's blocked a datagram or two even though I set the rule.. though it shows in the log that almost all are being allowed:


So it looks like 2 blocked to every 25 instead of 25 out of 25 blocked. Download speed seems unaffected by this small block.. and it's staying at max..

I'll still complain to F-Secure and ask for support but can I assume that this is now fixed?

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