ADO.NET Entity Framework: Update Wizard will not add tables
I had this problem too, all the above didn't work for me. What helped for me was the following.
When you try to connect with a database that database can have different users with different credentials it can accept. Let's say user A till D.
If you try to connect with a user make sure that user has the right credentials enabled, in this case, read and write options enabled.
To do this start MS SQL Server Managment Studio, connected with your SQL server and select the database you try to make a connection with in visual studio. Under 'your_dbname' --> Security --> Users you find a list of users. Rightclick the username you try to login with and select properties. A window opens. Select the 'General' (selected by default) page and under tab 'Database role membership' make sure 'db_datareader' and 'db_datawrite' are selected.
Note: When you log in too MS SQL Server Managment Studio make sure you log in with a user which can enable/disable these options...
The design surface is different from the entity model. It is possible to have a table in the mapping in your EDMX which does not appear on the design surface. View the file as XML to see if this is the case. In this case, the Update Wizard will not allow you to re-add the tables, since they are already part of the entity model. So, generally speaking, the Update Wizard knows more about your entity model than it does about the design surface, per se.
I don't think that's exactly the situation you're in, but it should give you the general idea for the solution: go into the XML and look for references to the tables in question.
Set Primary Keys to all tables or just one unchecked check-box "Allow null" to any column of each table. It works for me :)
Change the Table structure and add a Primary Column. Update the Model.
Modify the .EDMX file in XML Editor and try adding a New Column under tag for this specific table. (WILL NOT WORK)
Instead of creating a new Primary Column to Exiting table, i will make a composite key by involving all the existing columns.(WORKED)
Entity Framework: Adding DataTable with no Primary Key to Entity Model.