some users cannot see the Parts in the Impact Matrix grid for Express ECO.
I checked permissions but I couldn't find the exact place to fix it.
Where should I look?
Are those users able to see the parts through the main search grid? If so I'd recommend checking out the permissions on the Affected Item ItemType. It's possible a specific Identity does not have get access to affected items which could lead to this kind of behavior. I'd also check the permissions associated with part.