I am having the same problem; the manual states that it doesn't have write access to %appdata%\Juniper Networks\network connect. But my current login user does and so like most things Juniper its a load of rubbish. I suspect what';s happen as is often the case with Microsoft rubbish and that is Uncle Bill has discovered another security issue and gone about patching the problem with little to no regards as to what else the patch stops working, and Juniper being Juniper are draging there fleet on make an update or fix to make there software work properly; I hate the lot of them!!!
We are having the same problem. In our case, if you leave that window up, the VPN client is actually still connected. Is that the case for you? If you hit yes or no it disconnects us, but if you leave the window UP, the VPN is connected for us.
It is only affecting a few of our users, not all of them though. We recently pushed the latest Windows Updates out to PCs.
Let me know, please.