HIPS patch 6 refuses to install on some workstations. The only way I can get it to install is to go to each workstation and use 'update now' on the ePO agent. Despite there being a task to install the patch (and indeed it does work on some machines in the same part of ePO) the agent wake-up doesn't seem to trigger the update.
I've tried re-deploying the agent and removing it but nothing seems to get these clients to update via ePO.
What is the difference between using the agent 'check/enforce new policies' and the 'update now' on the workstation?
I would try deleting the agent install task and creating a new one.