An ASP.NET Web Application MVC in C# with Individual Accounts authentication has been created using a local file database. All account tables were automatically created, and user accounts were tested successfully. The website is running fine at this stage.
After adding the EDMX model using the ‘Model First’ approach with a sample entity table, the error message “An item with the same key has already been added.” is displayed when attempting to ‘Generate Database from Model…’.
Has anyone encountered a similar issue?
.Net Framwork 4.7.2, EF 6.4.4
Windows 10 Pro (Build 19045) and the same on Windows 11 Pro (Build 22631)
Visual Studio Community 2022 (64-bit) v. 17.10.3
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