Issue Scenario

A user tries to install our package on his org and gets the error – “Unable to install due to insufficient privileges”.

Possible Causes

Salesforce has a restriction on the access level  a user should have before trying to install an app exchange package.

Solution

Refer the Salesforce help document in the URL mentioned below that provides details on the access level that is required to install an app – https://help.salesforce.com/articleView?id=distribution_installing_packages.htm&type=5