One of my clients recently installed dasblog. While the overall installation was exceptionally painless, the “Mail to Weblog” feature refused to work within the customers environment. After much hair pulling, we were able to track the issue down to an IPV6 issue within the POP3 handling of the Mail to Weblog feature.
The customer’s environment consisted of an edge server running IIS7 and the exchange POP3 client on a single Hyper-V image. The Exchange server was a standard install on a Hyper-V image running standalone on bare iron.
Whenever dasBlog would activate, the log file would contain an error line of Pop3ServerError: System.Net.Sockets.SocketException: An address incompatible with the requested protocol was used fe80::8d30:bd51:31d9:60ac%15:110.
This particular client is IPV4 centric…which confused us in that the error contained an IPV6 address. Upon closer examination, all IPV6 protocols were active within exchange and the firewall was open for port 110 on both IPV4 and IPV6 protocols so the IPV6 address should not have been blocked. This was not making sense. To confound us even more, we were referencing the actual server by name (In this case edgeserver.clientsdomain.com) which returned an IPV4 address from the DNS.
OK.. so where was the IPV6 address coming from and why was it causing POP3 problems?
After a bit of network sleuthing, it appeared the Hyper-V Virtual Machine bus was translating the IP into a localhost call. The localhost call within Hyper-V then translated the IP address into an IPV6 address from the lmhosts file.
We removed the IPV6 address from the server’s hosts file. To remove the IPV6 localhost IP, perform the following actions:
Locate the hosts file at
Comment out the ::1 IPV6 address. Your entries should look like this when completed
We did not have the time to research why the call to the POP3 service was failing under IPV6. Our guess is the Lesnikowski routines may not be IPV6 compliant or there maybe an ASP.NET trust issue. With the Web Mail feature now working under IPV4, we declared victory and headed for coffee!
Full Error Text
code 650 message <span>Pop3ServerError:<br/>System.Net.Sockets.SocketException: An address incompatible with the requested protocol was used fe80::8d30:bd51:31d9:60ac%15:110
<br> at System.Net.Sockets.Socket.DoConnect(EndPoint endPointSnapshot, SocketAddress socketAddress)
<br> at System.Net.Sockets.Socket.Connect(EndPoint remoteEP)
<br> at Lesnikowski.Pawel.Mail.Pop3.Pop3.Connect()
<br> at newtelligence.DasBlog.Web.Services.MailToWeblog.Run()<br/> while processing .</span>