Thunderbird being blocked

I have been using Thunderbird for some time with no problems. Until now. Lately Thunderbird has refused to send or receive Emails.

Eventually I found that by turning Comodo off I could send Emails.

Security/Application Monitor shows Thunderbird allowed both In and Out.

Security/Network Monitor has Block & Log IP In/Out [Any]Source [Any]Destination ‘where ipproto is any’ (no idea what that means!)

Once, but only once, defining Thunderbird as a new Trusted Application worked for a couple of days. It has stopped again.

What do I do next?

G’day Terry,

Is there anything relevant in the logs?

If not, go to the network monitor, enable logging on all rules, start Thunderbird and try to send or receive emails. After it fails, go back to the Network Monitor and turn off logging for all rules except the bottom one (which should be the block all rule).

If you then look at your logs you should be able to pick out the bits where it blocked Thunderbird. Post that chunk of the logs here and we’ll see what we can figure out.

Ewen :slight_smile:

Thanks for the reply, Ewen.

Late yesterday I realised I could invoke System Restore and get back to where I was before all this happened. So I can’t do what you suggest. However I do still want to know what I did wrong. Probably misunderstood one of the warning messages Comodo keeps sending me.

I dug around in the logs, and found the following. I think it is the bit of the log you were referring to. Does it tell you anything? Or must I wait until this happens again? I could always undo the System Restore. :-((

If it helps, is the address of the router I am using.


C:\Program Files\Thunderbird\thunderbird.exe
C:\WINDOWS\explorer.exeB Application Access Denied (thunderbird.exe: :dns(53))Đ Description: Application Access Denied (thunderbird.exe: :dns(53))

Application: C:\Program Files\Thunderbird\thunderbird.exe

Parent: C:\WINDOWS\explorer.exe
Protocol: UDP Out


Hey Terry,

Port 53 is used for DNS (Domain Name Services) and is what translates our ""s into’s.

Make an additional rule in network monitor with the following parameters;

Action : ALLOW
Protocol : TCP or UDP
Direction : OUT
Source IP : ANY
Destination IP:
Source Port : ANY
Destination Port : 53

That should nail it on the head.

Ewen :slight_smile:

P.S. Did you guys REALLY get beaten by Bangladesh at the World Cup?? LOL. Oh the humanity!

Thanks, Ewen.

Done that; let’s hope that fixes it.

BTW, we don’t CARE who beats us - as long as it isn’t the Aussies! - LOL


LOL! I wonder what the Yanks on here think of the concept of a World Series that actually has the World in it? LOL

Ewen :slight_smile: