Microsoft Access System Tables

Understanding, Showing, Hiding, and Querying MSysObjects & System Metadata

You are browsing your tables in Microsoft Access when suddenly you notice a list of greyed-out tables with names starting with MSys.... Fear not — these are not malware or corrupt add-ins.

These are Microsoft Access System Tables. Typically hidden in the background, they contain vital structural metadata required for the Access database engine to run.

Table of Contents

Showing & Hiding Access System Tables

Read-Only Safety Notice: Access System Tables are strictly read-only. Never attempt to manually edit, insert, or delete records in MSys tables, as doing so can permanently corrupt database schema integrity.
Access 2007, 2010, 2013, 2016, 2019 & Microsoft 365
  1. Right-click the top header bar of the Navigation Pane.
  2. Click Navigation Options... from the context menu.
  3. In the Display Options area, check or un-check Show System Objects.
  4. Click OK to apply changes.
Access Navigation Options Dialog displaying System Objects configuration Click to enlarge
Legacy Access (2000, 2002 / XP, and 2003)
  1. Select Tools > Options from the top menu bar.
  2. In the Options dialog, select the View tab.
  3. Under the Show section, check or un-check System objects.
Legacy Access Options View Dialog showing System Objects checkbox Click to enlarge

What Does Each System Table Do?

MSysObjects
The master directory of the database. Contains one row for every table, query, form, report, macro, module, and linked data source in the database.
MSysQueries
Stores internal query definitions, parsed SQL components, joins, and output parameters indexed by ObjectID.
MSysRelationships
Stores table relationship configurations, foreign keys, and referential integrity constraints defined via the Relationships window or DAO.
MSysIMEXSpecs & MSysIMEXColumns
Store saved Import/Export specifications and column-level mapping definitions for flat files, CSVs, and Excel imports.
MSysAccessObjects
Internal repository tracking form and report design controls and property states.

MSysObjects Object Type Matrix

The Type column in MSysObjects identifies the specific classification of each database asset:

Type Column Value Database Object Type
1Local Table
4Linked Table (ODBC / SQL Server / MySQL)
5Query (Select, Action, Union)
6Linked Table (Access / Excel / Text)
-32768Form
-32764Report
-32766Macro
-32761VBA Module
2, 3, 8Access Reserved System Internal

Using System Tables in Your Databases

Querying MSysObjects directly provides a lightning-fast way to retrieve object catalogs without complex DAO/VBA loops.

For example, to populate a custom combo box or dropdown form control with all user-created Reports, set the control's RowSource property to:

SELECT [Name] FROM [MSysObjects] WHERE [Type] = -32764 AND Left([Name], 1) <> "~" ORDER BY [Name];
Why filter out Left([Name], 1) <> "~"?
Access creates temporary system artifacts and working query definitions prefixing with a tilde (~). Excluding these ensures users only see actual database reports.