Could not load file or assembly Microsoft.Office.Interop.Access.Dao ...

Problem

You see an error message like this when attempting to use a Microsoft Access database to create an application:

Failed to connect to the database server ...

Could not load file or assembly Microsoft.Office.Interop.Access.Dao, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c or one of its dependencies. The system cannot find the file specified.

You are trying to use a Microsoft Access database for your application and Iron Speed Designer could not find run-time support for Microsoft Access on your machine.

Solution

Either switch to a different database type or download run-time support for Microsoft Access. Runtime support for Microsoft Access can be found at:

Access 2007 Download: Access Run-time

http://www.microsoft.com/downloads/en/details.aspx?familyid=D9AE78D9-9DC6-4B38-9FA6-2C745A175AED&displaylang=en

Microsoft Access 2010 Run-time

http://www.microsoft.com/downloads/en/details.aspx?FamilyID=57A350CD-5250-4DF6-BFD1-6CED700A6715&displaylang=en

For a discussion of the differences in the versions of Microsoft Access, see “Backward Compatibility between Access 2010 and Access 2007”:

http://msdn.microsoft.com/en-us/office/cc907897.aspx