All fields grayed out when editing a project or task in client setup

When you try to modify a project or task on the
Projects
tab on the Clients screen, all the fields are grayed out and you can't change any data.
The most common reason you're unable to edit a project or task on the
Projects
tab is because you haven't enabled editing any client information by selecting the
Edit
option after the list of clients.
There is an
Edit
option in the
Projects
tab. That
Edit
button will open the selected project, but you can't modify any of the fields. To edit the project, you need to first select the
Edit
option following the list of clients.