As stated I have the ProBook 440 G1 which came with Windows 8.
Instead of updating via Windows I installed Windows 8.1 afresh, I didn't like the way the HDD was partitioned so I reformatted the whole HDD.
The installation went well and so did the core drivers, but the HP Client Security installation fails with an "Error 1001" and I am unable to use the fingerprint sensor.
The setup I downloaded was from HP's support page for Windows 8.1 x64 but I always get this problem, even after restarts and even a fresh Windows install.
I don't know what I'm doing wrong but would be grateful if someone could help me on this.