Microsoft KB Archive/140406

= ACC: How Microsoft Access Uses Encryption =

PSS ID Number: 140406

Article Last Modified on 5/7/2003

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The information in this article applies to:


 * Microsoft Access 1.0
 * Microsoft Access 1.1
 * Microsoft Access 2.0
 * Microsoft Access for Windows 95 7.0

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This article was previously published under Q140406



SUMMARY
Advanced: Requires expert coding, interoperability, and multi-user skills.

This article discusses how encryption is used in Microsoft Access.



MORE INFORMATION
Encryption enables you to prevent anyone from using a utility program or word processor to read and write data in a Microsoft Access database (.mdb) file. This feature is different from Microsoft Access security (which sets user and group permissions on database objects); its sole purpose is to make a database indecipherable by a file or disk editor.

Microsoft Access uses an RC4 encryption algorithm with a 32-bit key from RSA Data Security Incorporated. If you are creating an international application, this algorithm is acceptable for export outside of the United States (according United States export laws) because the key is less than 40-bits.

When you encrypt a database, all objects (tables, forms, queries, indexes, and so on) are affected because encryption is implemented at the page- level and not at the data-level. Microsoft Access encrypts a database in 2K (kilobyte) pages, regardless of the data stored in a page. Each encrypted page is assigned a unique 32-bit key.

Keywords: kbinfo kbusage KB140406

Technology: kbAccess100 kbAccess110 kbAccess200 kbAccess700 kbAccess95Search kbAccessSearch kbZNotKeyword3

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