Case Assignment insufficient privileges

Question

I have the following use case:

1. A manager creates a case in Salesforce (manager is case owner).
2. Send email from the inside the case.
3. Closes the case.
4. Manager assign case back to support queue.
5. The support rep (below manager in the role hierarchy) reassigns the case from the queue to himself.
6. Tries to reply to an incoming email.
7. Gets insufficient privileges notification.

Sharing setting for case is private and Grant Access Using Hierarchies. Any suggestions why I get insufficient privileges?

Answer 1

I suspect the "support rep" is not allowed to view (=use) the Contact on that case. Ask the support rep to click on the Case's contact. If I'm right he'll be slapped with "Insufficient priviledges" too.

1. Is the Contact manager's private contact (not linked to account)? Private contacts are visible only to owner & sysadmins, that's why you either use Accounts or B2C solutions (Person Accounts, Non profit Starter Pack etc). And no amount of sharing rules can amend that.
2. Check sharing. You should have the "Sharing" button on the Contact if it's not set to "Controlled by Parent". "Explode" the view and check if the list mentions the support rep.