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I am unable to start any SQL Server LocalDB instances on my Windows 11 Pro system (Build 22621.5624) with 32 GB RAM and an SSD with 4 KB+ physical sectors. I have tried both LocalDB 2017 (v14.0.1000.169) and 2019 (v15.0.4382.1), uninstalling/reinstalling, deleting leftover folders and registry keys, and running sfc /scannow, but every instance fails to start. Event Viewer shows repeated crashes of sqlservr.exe with ntdll.dll and exception code 0xc0000005, and I also encountered SqlUserInstance.dll not found (Windows error 126). My goal is to use Dataverse in Visual Studio, which requires a working LocalDB, and I need guidance on how to resolve this issue or workarounds to enable development.
You should have a file C:\Users\YourUsername\AppData\Local\Microsoft\Microsoft SQL Server Local DB\Instances\MSSQLLocalDB\error.log.
If you see a message about 256 misaligned reads, you are running into a known issue where Windows 11 for some disk drives reports a sector size that SQL Server does not cope with. Microsoft has published an article with workarounds for the problem.
If you don't see the message about misaligned reads, attach the error.log file here so we can look at it.