Custom Report Type is missing fields related via Lookup

While it is possible to add fields related via lookup to a Custom Report Type, your report may not contain results for all of the related fields.
 

Example scenarios

A report does not display any results when...
 

• A lookup field is used as a report filter and the running user does not have permission to view this field
• A formula field that references the field from the lookup object is used, and the running user does not have permission to view this field

Records do not appear in a report if...
 

• The affected user does not have access to the lookup object's records
• The report filter has multiple values, and only one is meeting the criteria (in this scenario, only records the user has access to will display)

In these scenarios, an affected user can remove the filter to see all lookup field values and the object's records containing the lookup field, but they will not be able to see any fields added via this lookup when creating, customizing, or viewing a report.