PC DB: Description of Mail Database Subdirectories

The information in this article applies to:

• Microsoft Mail for PC Networks, versions 2.1x, 3.0, 3.2

This article provides descriptions of each of the Mail database subdirectories. It also lists the versions of Mail in which that subdirectory exists.

If a customer is experiencing a problem, the Mail administrator should NEVER modify file sizes without first consulting with Microsoft Product Support Services.

The following is a brief description of the database subdirectories (where appropriate, default file sizes are listed):

Subdir    Description                                            Version(s)

ATT       This subdirectory has 16 subdirectories that contain         All
          any attachment files that are used in the Mail system.
          Each of the 16 subdirectories contain encrypted
          attachment files. Files that have the .ATT extension are
          files that have been attached to a particular mail item.
          The reference to an attachment file is in the mail (.MAI)
          file itself. A single mail file can reference several
          attachments, but a single attachment file cannot be
          referenced more than once.

CAL       This subdirectory stores the online calendar files when      3.0
          Schedule+ is installed. The files are stored according       3.2
          to a hexadecimal (hexid) number that is assigned when
          the Schedule+ user first logs on.

          NOTE: The hexid number is NOT the same number as the
          one used by the Mail system!

FOLDERS   This subdirectory is used by the folders subsystem.          All
          All folder files are stored here initially. Mail users
          may optionally move individual private folders to local
          storage. Individual private folders are stored in the
          FOLDERS\LOC\<hexid> subdirectory. Group and shared
          folders are stored in the FOLDERS\PUB subdirectory. This
          storage method is used by all versions of the MS-DOS
          client, OS/2 client, and Macintosh client. It is also
          used by the version 2.1 Windows client.

          the <serialno>.IDX file in the FOLDERS subdirectory is
          4 bytes (fixed size). Individual <nnnnnnnn>.IDX files
          and the FOLDROOT.IDX file are (file size - 100 bytes) and
          should be divisible by 158.

GLB       The files in this directory are at the top of the            All
          hierarchy of the database and serve a variety of
          purposes. These files contain the core of the postoffice
          configuration. The GLB directory also contains error
          message and other types of files that do not contain
          postoffice configuration information. This is also the
          default location for modem scripts.

          File Sizes
          ----------

          ACCESS.GLB should be divisible by 586.
          ACCESS2.GLB should be divisible by 69.
          ACCESS3.GLB should be divisible by 512.

          The result for the three access files should be the same
          number.

          CONTROL.GLB    8 bytes fixed size
          FLAG.GLB       2 bytes fixed size
          GLOBAL.GLB     512 bytes fixed size
          GROUP.GLB      (file size - 4 bytes)
                         Should be divisible by 51
          GRPMEM.GLB     (file size - 4 bytes)
                         Should be divisible by 128
          MASTER.GLB     176 bytes fixed size
          MODEM.GLB      64 bytes fixed size
          NETPO.GLB      (file size - 4 bytes)
                         Should be divisible by 43
          NETWORK.GLB    Should be divisible by 122
          PROCESS.GLB    (file size - 512 bytes)
                         Should be divisible by 197
          REQCONF.GLB    512 bytes fixed size
          SERVER.GLB     Should be divisible by 181
          SVRCONF.GLB    On directory synchronization server only
                         1024 bytes + (1024 bytes * total number of POs)
          TID.GLB        4 bytes fixed size

GRP       This subdirectory contains the group pointer files for       All
          public and private distribution lists.

          The file size should be divisible by 8.

HLP       This subdirectory contains the Help files for the            All
          individual Mail programs. Help is opened when the F1
          key is pressed.

INF       This subdirectory contains the information files that        All
          correspond to the postoffice-defined template files.
          The INF file contains template ("about") information for
          every user defined in a .USR file. The .USR file is the
          user list for external Mail for PC Networks postoffices
          and has the same filename prefix as the postoffice's MBG
          file. The .INF file also has this same filename prefix.
          There may also be an ADMIN.INF file if the local postoffice
          administrator has defined a custom template. External
          postoffice .INF files only exist if another postoffice
          administrator exports templates. The record format of the
          .INF file is defined by the associated .TPL file. There is
          always an associated .TPL file with every .INF file.

INI       This subdirectory is the default location for .INI files     3.2
          used by the system; notably, by the Dispatch and External
          Mail programs.

KEY       This subdirectory contains the index files that are used     All
          to determine the location of the mail header in the
          individual user's mailbag (.MBG) file. There will always
          be a corresponding .MBG file in the MBG subdirectory. The
          .KEY file contains information such as the number of new
          mail items since the user last logged in, the amount of
          unread mail in the user's mailbag, and a bitmap of deleted
          records in the corresponding .MBG file. The bitmap is used
          so that when mail is sent to a user, a vacant record
          position in the user's .MBG file can be found directly by
          examining the bitmap rather than having to sequentially
          process the .MBG file looking for deleted records.

          The file size should be 560 bytes (fixed size).

LOG       This subdirectory is the default location for the log        All
          files created by the External Mail, Dispatch, and other
          gateway programs. The creation of these files is
          determined by the parameters that are specified when the
          various programs are started.

MAI       This subdirectory has 16 subdirectories that contain         All
          any message files that are used in the Mail system. Each
          of the 16 subdirectories contains encrypted message files.

MBG       This subdirectory contains the individual mailbag files      All
          that are used to store the Mail headers for an individual
          user. It is basically the file format of the first screen
          a user sees when he or she starts up the MS-DOS Mail or
          Monitor program. There will always be a corresponding key
          index (.KEY) file in the KEY subdirectory.

          The records contained in the mailbag (.MBG) file serve two
          purposes:

           - A non-deleted record acts as an index pointer to a mail
             item. Thus, a single mail file can be pointed to by many
             mailbag records. Each of these mailbag records must
             reside in separate .MBG files because two records in a
             single mailbag can never point to the same item of mail.

           - .MBG records contain summary information about the
             particular mail item. This information is used by the
             user agent programs to display a list of mail headers in
             the opening display of the user's mail. The mail file
             itself does not have to be read until the user selects
             it for processing (for example, by reading, deleting, and
             so forth). There is no delete flag in the .MBG record
             structure. Deleted status is maintained in the .KEY file,
             which has the same filename prefix as the .MBG file.

          There is a single .MBG file for every local user, of the
          format <nnnnnnnn>.MBG; there is a single .MBG file for
          every external postoffice or gateway that is defined; and
          there is an INQUEUE3.MBG file that is used to receive any
          mail from external sources and an INQUEUE.MBG file that is
          used for directory synchronization (Dir-Sync).

          Mail is delivered from the INQUEUE3.MBG file to individual
          mailbags via the Mailer process. The version 3.0 postoffice
          contains a special mailbag: SYSTEM.MBG. Mail addressed to
          network/postoffice/$system will be put here. This mailbag
          is currently used for Dir-Sync mail, but in future versions
          it may also be used for other system mail functions.

          The file size should be divisible by 116.

MEM       This subdirectory contains only the local members of         All
          global groups defined at this postoffice. External
          addresses are not part of the member list. Each record
          represents a user mailbag number. These files are only
          created for administrator-defined groups (that is,
          postoffice groups) and are used for quick access by
          Mailer for resolving groups.

          The file size should be divisible by 4.
          The maximum size should 2000 bytes.


MMF       This subdirectory contains the Mail message files (.MMF)     3.0
          used by the Windows clients in versions  3.0 and later.      3.2
          These files are stored by user hexid number.

NME       This subdirectory contains the files for the postoffice      All
          address list (POL), the global address list (GAL),
          gateway address lists, and the individual personal address
          lists (PALs) used by all clients in version 2.1, and in
          the MS-DOS, OS/2, and Macintosh clients in Mail versions
          3.0 and later. The concept of these lists is to allow
          dissimilar address types to reside in the same address list.

          The file size should be divisible by 45.

P1        This subdirectory is used by the External Mail program to    All
          store temporary mail files during a communications or
          postoffice-to-postoffice (PO-to-PO) delivery session.

TPL       This subdirectory contains the template files used by the    All
          local postoffice and gateways.


USR       This file is the address list of users and groups for a      All
          particular postoffice. The postoffice that this list
          represents is an externally defined postoffice. If this
          file exists, its prefix filename will match the external
          postoffice's .MBG filename. This file can be created or
          updated using the Mail Administrator program (ADMIN.EXE)
          or it can be created or replaced by the External Mail
          program when it receives an exported user list from this
          postoffice.

          The file size should be divisible by 53.

XTN       This subdirectory contains the external postoffice           All
          definition files. Each .XTN file contains all of the
          postoffices that are defined at an individual network.

          For each network that is defined in the NETWORK.GLB file,
          there is an associated .XTN file. This file is a series
          of records, where each record defines a different
          postoffice at this network. The purpose of this file is
          to provide routing, naming, and sign-on information for
          external services/postoffices. Postoffice records also
          contain connection information, statistics, and various
          configuration options for that postoffice. Each postoffice
          record contains a file pointer reference to its mailbag.
          When an address list of users is created for this
          postoffice, there will also be a .USR file and, possibly,
          .TPL and .INF files with the same file prefix as the .MBG
          file.

          The file size should be divisible by 698.