I have this issue right now and it's not caused by any software. Since the first thing I downloaded on a brand new PC was Minecraft, no other software of any type (except the Windows 7 OS itself).
I still have this issue since 1.3.1, and I don't have K9 on my computer.
MS Windows 7 64-bit SP1Intel Pentium T4300 @ 2.1GHz3GB RAMMobile Intel 4 Series Express Chipset Family
It's a laptop, but that shouldn't make any difference to the issue.
Ans Farooq
I have this issue right now and it's not caused by any software. Since the first thing I downloaded on a brand new PC was Minecraft, no other software of any type (except the Windows 7 OS itself).