Which version are you using?
When 8.1 was clicked on me, my copy of Shrew 2.2.2 Professional completely stopped connecting with the message โdisconnect the tunnelโ (there were 3 messages, this is the only thing I can remember). He also shut down my virtual machine.
To fix, I deleted my virtual machines (VirtualBox, etc.), rebooted, reinstalled Shrew, rebooted, and then re-enabled the virtual machines. Now everything is working correctly.
NTN!
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