First Published 16 Mar 2024                                           Difficulty Level: Moderate

This article explores a relatively obscure area about which there is little or no official information

Individual user and wizard settings for Microsoft Access are stored in various places:

1.   Client settings in Access Options

      The preferences specified in Client Settings are stored in the registry at HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Access\Settings

      Although it is possible to edit the client settings data directly in the registry, there should normally be no reason to do so.

2.   Data used by Access wizards is stored in a hidden folder: C:\Users\YourUserName\AppData\Roaming\Microsoft\Access

      There are normally three databases in this folder:
a)   AccessCache.accdb (Access 2010 onwards)
b)   ACWZUSR12.ACCDU (Access 2007 onwards) / ACWZUSRT.MDT (Access 2000-2003)
c)   System.mdw (Access 97 onwards)
      There may be several similarly named files System1.mdw, System2.mdw etc

All of these files are needed for Access to work correctly and should not be deleted.
If any of these files are removed or deleted, replacement file(s) will be automatically created when an Access database is next opened or uses a feature that depends on them.

I will now discuss each of these files in more detail

a)   AccessCache.accdb (Access 2010 onwards)

      This small database is used to manage the Application Parts feature introduced with Access 2010. It contains two additional system tables: Category and Template

      The Category table contains the various categories listed in the Application Parts feature. The built-in Blank Forms / Quick Start items are always listed.
      If the user has created additional application parts, these will be listed under User Templates or User Defined Types

      For more details about this little used Access feature, see my article:Application Parts and Templates

b)   ACWZUSR12.ACCDU (Access 2007 onwards) / ACWZUSRT.MDT (Access 2000-2003)

      This is a much larger database which is used to manage data used by Access wizards

      In my copy of Access 365, it contains over 50 local tables

      Many of these tables may be empty, presumably where the wizard that depends on them has never been used.
      The tables that do contain data may therefore differ depending on the user. In my case, 30 of those tables do contain data:

      The information below outlines the purpose of these tables (where known):

Table Records Purpose
cw_tblChartTemplates 1 Stores the name of the chart object: Microsoft Graph Chart
doc_tblObjects 51 Database properties and permissions
doc_tblProperties 338 Object and control properties
doc_tblPropertyCategories 5 Property categories
im_TblInputMask 200 Details of all input masks by country / locale as used by the wizard
mlbl_tblLabelSizes 2540 Details of all labels as used by the label wizard
mlbl_tblMailingLabelPreferences 2 Labels specified previously?
mlbl_tblRepProperties 39 Properties used by the report wizard
tblControlStyles 7600 Control style info
tblFonts 81 Installed fonts?
tblLangFont 205
tblLanguages 9 Office languages installed now or in the past
tblLayoutStyles 1500
tblSectionStyles 750
tblStyles 50
UT_tblExportObjectList 26
UT_tblExprFixup 87 Expressions and replacements
UT_tblFieldExtProps 21 External properties for fields - Old name / new name
UT_tblJetCompoundKeywords 11 Keywords used in query SQL
UT_tblJetKeywords 99 Jet reserved words
UT_tblJetKeywordsThatNeedFixup 10 Jet key words
UT_tblJetKeywordsWithTableNames 4 Keywords used in query SQL before table names
UT_tblKeywords 275 Reserved words?
UT_tblReportIndexes 3 Geographical data
UT_tblReportMisc 1
UT_tblReportTables 1 Geodata
UT_tblSelectKeywords 10 Keywords used in SELECT query SQL
UT_tblTablesToExport 1
UT_tblTblExtProps 9 External properties for tables - Old name / new name
UT_tblXLATChars 1 ????

c)   System.mdw (Access 97 onwards)

      The original purpose of this file was to manage workgroup information in MDB files.
      Two read only system tables, MSysAccounts and MSysGroups, both containing unreadable data, manage this process

      However, the System.mdw file is always opened in the background and a lock file created as soon as any Access file is opened.
      This applies to any Access file type (ACCDB / ACCDE / ACCDR / MDB / MDE ) and includes Access files opened read only or exclusively.


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Colin Riddington                 Mendip Data Systems                 Last Updated 16 Mar 2024

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