Outlook s Files

Outlook's Files

Some informationOutlook uses is stored in files on your hard drive. Some of these files are viewable, some are editable, and some are neither. Table C.1 lists many of these files, the information they hold, and whether they're viewable and editable.

Table C.1. Outlook's Files

File	Information	Viewable	Editable
Extend.dat	List of Outlook add-ins and extensions	No	No
Filters.txt	Criteria for junk mail filtering	Yes	No
Frmcache.dat	Cache of form definitions	No	No
<profile name>.nk2	Stores addresses you've replied to for the Automatic Suggest Names feature (AutoComplete)	No	No
Outcmd.dat	Menu and toolbar customizations	No	No
OutlPrnt	Print settings	No	No
VBAProject.otm	VBA macro code	Yes	Yes
Views.dat	Information on custom views	No	No
Outlbar.inf	Outlook Navigation pane setup information	No	No

A large number of file extensions are associated with Outlook's files. Many of those extensions are listed in Table C.2 along with a few other common extensions you need to know.

Table C.2. Outlook's File Extensions

File Extension	File Type
.cfg	Form setup files
.chm	Help file
.csv	Comma-separated values files (Windows)
.dat	Menu and view settings
.dic	Spelling dictionary files
.dll	Applications extensions
.ecf	Extension configuration files
.eco	ECCO files
.exe	Executable files
.fav	Outlook Bar shortcuts
.fdm	Form message files
.htm	HTML files
.html	HTML and stationary files
.ics	iCalendar files
.inf	Profile settings, installation files, or multipurpose files
.mdb	Access files
.msg	Messages dragged onto the Windows desktop
.nk2	Nicknames
.ocx	ActiveX controls
.oft	Outlook templates
.oss	Saved searches
.ost	Offline storage files
.pab	Personal address book
.pag	Saved toolbox page
.pst	Personal folder and AutoArchive files
.rhc	Remote mail header file
.rtf	Document saved in rich text format
.srs	Send/receive settings
.stf	Setup table files
.txt	Tab-separated values files, comma-separated values files (DOS), and text files
.vcf	vCard files
.vcs	vCalendar files
.vfb	Free/busy files
.wab	Windows address book
.xls	Excel files
.xnk	Folder shortcuts

Each Outlook item type (message, meeting request, task) has its own file extension known as a message class. The message class of an Outlook item contains the definition for how the item is to be displayed. Without the proper message class, an item will not display as you might expect. When developing custom forms, you must start with a base message class and then customize your item into a different message class. However, even customized Outlook items still retain the base message class in their name. Table C.3 lists all the message classes for each Outlook item.

For more information about Outlook forms and message classes, see "Understanding Item Types and Message Classes," p. 759.

Table C.3. Outlook's Message Classes

Message Class	Item Type
IPM.Activity	Journal entry
IPM.Appointment	Appointment
IPM.Contact	Contact
IPM.DistList	Distribution list
IPM.Document	Document
IPM.Note	Email message
IPM.Note.Rules.Oof.Template.Microsoft	Show out of office templates
IPM.Note.Rules.ReplyTemplate.Microsoft	Edit rule reply template
IPM.Note.Secure	Encrypted note
IPM.Note.Secure.Sign	Digitally signed note
IPM.OLE.Class	Recurrence items and exceptions
IPM.Outlook.Recall	Retrieve sent message from recipient's inbox
IPM.Post	Post
IPM.Recall.Report	Message recall report
IPM.Remote	Remote mail message header
IPM.Report	Report item
IPM.Resend	Resend failed message
IPM.Schedule.Meeting.Cancelled	Meeting cancellation
IPM.Schedule.Meeting.Request	Meeting request
IPM.Schedule.Meeting.Resp.Neg	Decline meeting
IPM.Schedule.Meeting.Resp.Pos	Accept meeting
IPM.Schedule.Meeting.Resp.Tent	Tentatively accept meeting
IPM.StickyNote	Note
IPM.Task	Task
IPM.TaskRequest	Task request
IPM.TaskRequest.Accept	Accept a task request
IPM.TaskRequest.Decline	Decline a task request
IPM.TaskRequest.Update	Update a task request