I have a custom object, say CS in my org. User U1 has profile P1 and P1 has all the crud permission on that object. Still while logging as U1, and try to query that particular object it errors out : sObject type is not supported. Can anyone help what other permission needs to set in order to make that particular custom object queryable for that profile ? thanks in advance
Please check if one of below things resolve your issue.
Make sure there exists a object with API name that you are using. Most likely you are mistaking the object API name. Go to setup > create> Object and check the API name.
Go to profile level and check if 'API Enabled' permission is checked.
In your screenshot - The status of the object shows that its in development. This is the issue.