When using a Microsoft Access Database (*.mdb file) as a data source in ASP.NET it is necessary to grant physical Write access for the ASP.NET user to the .mdb file and to the directory where that .mdb file is stored.
If you are using MS Access you might run into database lock issues.
Specific error message: "Operation must use an updateable query."
The most common reason for this error is that the Internet Guest account (ASPNET user), which is by default part of the "Everyone" group, does not have Write permissions on the database file (.mdb). To fix this problem, use the Security tab in Explorer to adjust the properties for this file so that the Internet Guest account has the correct permissions.
When using Microsoft Access databases, it is also necessary to give the Internet Guest account Write permissions on the directory containing the .mdb file. This is because Jet creates an .ldb file to handle database locking.
You may also need to give read/write permission on the "Temp" folder because the Jet database enginge may create temporary files in this directory.
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