You are using Microsoft Access and receive an error in the event viewer saying:
ďThe Microsoft Jet database engine cannot open the file 'C:\MyApp\YourDatabaseName.mdb'. It is already opened exclusively by another user, or you need permission to view its data.Ē
Review this Microsoft Knowledge Base article:
This article discusses one possible cause:† The ASP.NET worker process runs under the default ASPNET account. If you do not enable impersonation for an application, all of the threads that run the requests for that application run under the process account.
This article suggests several solutions:
Configure the ASP.NET worker process to run under the SYSTEM account in the <processModel> section of the Machine.config file.
For security reasons, Microsoft recommends that you enable impersonation on your ASP.NET application. This method works if the impersonated user has necessary permissions to the computer and the database that you are accessing. †See Cannot Connect to Your Database.
Grant read and write permissions for the "Everyone" group on the database and the database folder. This method is not safe; therefore, Microsoft does not recommend this method.
Please also take special note of the following:
Microsoft Access databases can only be located on the local drive.† This is a restriction of the Microsoft JET driver and not of Iron Speed Designer.
Make sure the MDB file is not set to Read-Only.† This is perhaps the most common cause of problems with Microsoft Access databases.
They can be located in any folder on the local drive, but the folder must have Read/Write permission for the ASPNET user.† Go to Windows Explorer and add the ASPNET user to have Full permissions on the folder containing the MDB file.
The path specified in the Web.config must be a fully specified path.† Relative paths in the Web.config file are supported starting with Version 2.1.2 of Iron Speed Designer.
Application Runs But No Data is Displayed