I can reproduce.
Steps:
1) Download and install mIRC.
2) Close your browser, clearing history/cookies/cache/etc.
3) Connect to freenode: /server -m chat.freenode.net:+7000
4) Join around 50 random channels. [Note 1, 2]
5) Do /timer1 4 1 /amsg test or something else to get yourself flooded off the network via excess flood.
6) Go to imgur.com and open up as many images as you can.
7) During the reconnection or immediately after, mIRC will disconnect with [10101] Host disconnected
If that didn't work:
8) Load imgur.com, closing all other tabs.
9) Clear your cookies/history/cache/etc.
10) Open as many images as you can at once.
11) At some point, mIRC should disconnect with [10101] Host disconnected. You may need to make mIRC the active application before it does.
mIRC won't disconnect if you use a non-ssl port.
Note 1: I say ~50 because that is how many channels I idle in. This will still work/disconnect even if you are in 1 channel.
Note 2: I recommend doing //join ## $+ $rand(0,9) $+ $rand(0,9) $+ $rand(0,9) $+ $rand(0,9) $+ $rand(0,9) to join channels without anyone else in them.
