If you have many VPN clients (or network filters) installed on your system, Junos Pulse install may fail due to low maxfilters value in registry. Install hangs for some time and then rolls back.
If rollback is interrupted, or if install is triggered by web-installer it results is non-working VPN client with empty connection window.
This means that necessary services to run the clinet are missing – only UI files are installed.

To resolve the issue, you need to edit the Windows Registry key:
[code]HKLM/SYSTEM/CurrentControlSet/Control/Network/MaxNumFilters[/code]

This value defines the maximum number of network filter drivers allowed on the computer.

Try to change this value to 14 (maximum value), and the Junos Pulse install should finish successfully.

Source: http://forums.juniper.net/t5/SSL-VPN/Junos-Pulse-empty-window-Win-7-64-bit/td-p/96592/page/3