The PIR Search first has to be enabled with a Security Profile permission and then needs to be enabled by the individual user in their web preferences too.
To enable the PIR search for all users in a specific profile:
Log in to FocalPoint Administrator
Browse to System Control, Security Profiles.
Select the relevant security profile
Click Edit
Click on the Security tab
Select the Authorisation node
Double-Click on Invoice Register in the right-hand pane to enable it
Click OK to save
Then, to enable the PIR search for a specific user:
Log in to the FocalPoint website as the user who needs this access
Click on the user name in the top right
Select Preferences
Scroll down to find the Invoice Register section
Ensure that Show PIR Search is ticked
Click Save at the top of the page
Log out and back into the FocalPoint website to pick up the changes