Article ID: 195475
Article Last Modified on 10/15/2003
APPLIES TO
- Microsoft OLE DB Provider for Jet 3.51, when used with:
- Microsoft Data Access Components 2.0
This article was previously published under Q195475
SYMPTOMS
Opening the connection on a read-only Microsoft Access Database (.mdb file
on a CD-ROM, a floppy disk that is write protected, or a hard disk that is
read-only to the user, and so forth) with the following code causes an
error to occur. The following code opens a connection on a Microsoft Access
database file on a CD-ROM:
Dim con as new ADODB.Connection
con.Provider = "Microsoft.Jet.Oledb.3.51"
con.Open "Data Source=E:\testdb.mdb"
It causes the following error:
The Microsoft Jet database engine cannot open the file E:\testdb.mdb.
It is already opened exclusively by another user, or you need
permission to view its data.
CAUSE
The Jet OLEDB provider opens databases, by default, in Read/Write mode. Jet
requires the creation of a locking file (.ldb file) in order to open a
database file in shared access mode. If you request shared access mode, Jet
attempts to create the locking file, which fails on read-only media. If you
open a database using exclusive mode, Jet does not need to create the
locking file.
RESOLUTION
Open the database in read-only and exclusive mode. You can do this by
setting the Mode property of the connection object to adShareDenyWrite.
The following code opens a connection on a read-only Microsoft Access
database:
Dim con as new ADODB.Connection
con.Provider = "Microsoft.Jet.Oledb.3.51"
con.Mode = adShareDenyWrite
con.Open "Data Source=E:\testdb.mdb"
REFERENCES
The following Microsoft Knowledge Base article describes the same problem
and a resolution when using Data Access Object (DAO):
191737
PRB: DAO MDB on Read-Only Media Must Be Opened Exclusively
Microsoft Developer Network Library, Visual Studio 6.0; search on:
Microsoft Data Access SDK
Keywords: kbdatabase kbjet kbprb KB195475