Use the following list of troubleshooting topics to quickly find information to solve your Dynamics 365 Sales lead-related issues.
Lead Qualification Issues and Resolution
Issue:- Insufficient permission or access denied error when a user is trying to qualify a lead.
Scenarios:- How you resolve the error depends on the following ownership scenarios for the lead records.
- The lead that the user is trying to qualify is in their business unit.
- The lead is owned by the user trying to qualify it.
- The lead that the user is trying to qualify is in their organization.
Resolutions:-
Scenario 1: The lead that the user is trying to qualify is in their business unit.
Step 1:- Navigate to Settings -> Security -> Security Roles.

Step 2:- Open assigned user security role. (In our case security role is “Sales Person”).
Step 3:- On Core Record tab Assign Create, Read, Append, and Append To permissions to the user ’s Security Role at Business Unit level on the following entities:
a. Account
b. Contact
c. Lead
d. Opportunity

Step 4:- Assign Read access to any custom entity on Custom Entities tab.
Step 5:- Assign Read access to Attribute Map, Customization’s, Entity Map on Customization tab.
Scenario 2:- The lead is owned by the user trying to qualify it.
Step 1:- Navigate to Settings -> Security -> Security Roles.

Step 2:- Open assigned user security role. (In our case security role is “Sales Person”).
Step 3:- On the Core Records tab, assign Create, Read, Append, and Append To permissions to the Security Role at User level on the following entities:
a. Account
b. Contact
C. Lead
d. Opportunity

Step 4:- On the Customizations tab, assign Read access to Attribute Map, Customizations, Entity and Entity Map.
Step 5:- Assign Read access to any custom entity On the Custom Entities tab.
Scenario 3:- The lead that the user is trying to qualify is in their organization.
Step 1:- Navigate to Settings -> Security -> Security Roles.

Step 2:- Open assigned user security role. (In our case security role is “Sales Person”).
Step 3:- Assign Create, Read, Append, and Append To permissions to the user’s Security Role at Organization level on the following entities:
a. Account
b. Contact
c. Lead
d. Opportunity

Step 4:- Assign Read access to any custom entity On the Custom Entities tab.
Step 5:- On the Customization tab, assign Read access to Attribute Map, Customization’s, Entity and Entity Map.
I hope this will help you.
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