The 80004005 error occurs when you try to use ActiveX Data Objects (ADO) or ODBC to connect to a Microsoft Access database. The error you may receive will look something like this:
“The Microsoft Jet Database Engine cannot open the file ‘(unknown)'”
“Microsoft OLE DB Provider for ODBC Drivers error ‘80004005’
[Microsoft][ODBC Microsoft Access 97 Driver] The Microsoft Jet database engine cannot open the file ‘(unknown)’. It is already opened exclusively by another user, or you need permission to view its data.”
What Causes The 80004005 Error
There are several causes of the 80004005 error, some of which include:
- The account that Microsoft Internet Information Server (IIS) is using (which is usually IUSR) does not have the correct Windows NT permissions for a file-based database or for the folder that contains the file.
- The file and the data source name are marked as Exclusive.
- Another process or user has the Access database open.
How To Fix The 80004005 Error
Step 1 – Check The Permissions On The File
It is recommended that you check the permissions on the file and the folder. Make sure that you have the ability to create and/or destroy any temporary files. Temporary files are usually created in the same folder as the database, but the file may also be created in other folders such as the WINNT folder.
Step 2 – Verify The File And Data Source
It is important to verify the file and data source because the file has to be in proper working order and must be protected from damage or corrupt. Other wise your computer will experience some difficulty trying to use the correct files.
Step 3 – Close Any Visual InterDev Projects
It is recommended that you close down any other Visual InterDev projects that contain a data connection to the database. This way your computer won’t be confused and will be able to work properly.
Step 4 – Clean Out The Registry
One of the big causes of 80004005 errors is through the “registry” database of your computer. This is a large database which stores vital information & settings for your PC, and is used continually to help Windows to read the files, settings & options that it needs to run. Although the registry is one of the most important parts of every Windows system, it’s continually causing a large number of problems thanks to the way it will often become corrupted and unreadable. This is the cause behind many 80004005 errors, and needs to be resolved by using a reliable “registry cleaner” application.
This step is best completed by downloading Frontline Registry Cleaner, and letting it clean out any of the problems that your system may have inside.