MORE INFORMATION
A look in the Active Directory gives a much better view of the difference between a User and a Contact. Attributes for User and Contacts for all possible cases are defined below:
Windows 2000 User with no mail-enabling or mailbox-enabling
Windows 2000 User with mailbox-enabled
Windows 2000 User with mail-enabled
Windows 2000 Contact with no e-mail address
Windows 2000 Contact with target e-mail address defined
The most important aspect of the differences between the User and Contact are the fact that the User has several attributes,
SAMAccountName,
objectSID,
userAccountControl, and
userPrincipalName, which allow the User to log on. The Contact does not have these attributes. Notice also, the differences in the attributes defined for the two Contact types:
Windows 2000 User - No Mail-enabling or Mailbox-enabling
First Name: John
Last Name: Doe
User Logon Name: jdoe
>> Dn: CN=John Doe,CN=Users,DC=pique,DC=extest,DC=microsoft,DC=com
1> accountExpires: 9223372036854775807;
1> badPasswordTime: 0;
1> badPwdCount: 0;
1> codePage: 0;
1> cn: John Doe;
1> countryCode: 0;
1> givenName: John;
1> instanceType: 4;
1> lastLogoff: 0;
1> lastLogon: 0;
1> logonCount: 0;
1> distinguishedName: CN=John Doe,CN=Users,DC=pique,DC=extest,DC=microsoft,DC=com;
1> objectCategory: CN=Person,CN=Schema,CN=Configuration,DC=pique,DC=extest,DC=microsoft,DC=com;
4> objectClass: top; person; organizationalPerson; user;
1> objectGUID: 0fcbed12-00d2-11d3-a9c5-00c04f68099e;
1> objectSid: S-15-323E04BE-1898D11E-2B3BE507-457;
1> primaryGroupID: 513;
1> pwdLastSet: 125701524342968750;
1> name: John Doe;
1> sAMAccountName: jdoe;
1> sAMAccountType: 805306368;
1> sn: Doe;
1> userAccountControl: 66048;
1> userPrincipalName: jdoe@pique.extest.microsoft.com;
1> uSNChanged: 6459;
1> uSNCreated: 6453;
1> whenChanged: 5/2/1999 14:0:34 Pacific Standard Time Pacific Daylight Time;
1> whenCreated: 5/2/1999 14:0:34 Pacific Standard Time Pacific Daylight Time;
1> msExchMailboxSecurityDescriptor: <ldp: Binary blob>;
Windows 2000 User - Mailbox-enabled
First Name: John
Last Name: Doe
User Logon Name: jdoe
Alias: jdoe
>> Dn: CN=John Doe,CN=Users,DC=pique,DC=extest,DC=microsoft,DC=com
1> homeMDB: CN=Private MDB,CN=First Storage Group,CN=InformationStore,CN=KINDC,CN=Servers,
CN=First Administrative Group,CN=Administrative Groups,CN=OR1,CN=Microsoft Exchange,
CN=Services,CN=Configuration,DC=pique,DC=extest,DC=microsoft,DC=com;
1> accountExpires: 9223372036854775807;
1> badPasswordTime: 0;
1> badPwdCount: 0;
1> codePage: 0;
1> cn: John Doe;
1> countryCode: 0;
1> displayName: jdoe;
1> mail: jdoe@pique.extest.microsoft.com;
1> givenName: John;
1> instanceType: 4;
1> lastLogoff: 0;
1> lastLogon: 0;
1> legacyExchangeDN: /o=or1/ou=first administrative group/cn=Recipients/cn=jdoe;
1> logonCount: 0;
1> distinguishedName: CN=John Doe,CN=Users,DC=pique,DC=extest,DC=microsoft,DC=com;
1> objectCategory: CN=Person,CN=Schema,CN=Configuration,DC=pique,DC=extest,DC=microsoft,DC=com;
4> objectClass: top; person; organizationalPerson; user;
1> objectGUID: a8ecb576-00d2-11d3-a9c5-00c04f68099e;
1> objectSid: S-15-323E04BE-1898D11E-2B3BE507-458;
1> primaryGroupID: 513;
2> proxyAddresses: SMTP:jdoe@pique.extest.microsoft.com; X400:c=us;a= ;p=PIQUE;o=OR1;s=Doe;g=John;;
1> pwdLastSet: 125701526912031250;
1> name: John Doe;
1> sAMAccountName: jdoe;
1> sAMAccountType: 805306368;
1> showInAddressBook: CN=Default Global Address List,CN=All Global Address Lists,
CN=Address Lists Container,CN=OR1,CN=Microsoft Exchange,CN=Services,
CN=Configuration,DC=pique,DC=extest,DC=microsoft,DC=com;
1> sn: Doe;
1> textEncodedORAddress: c=us;a= ;p=PIQUE;o=OR1;s=Doe;g=John;;
1> userAccountControl: 66048;
1> userPrincipalName: jdoe@pique.extest.microsoft.com;
1> uSNChanged: 6468;
1> uSNCreated: 6462;
1> whenChanged: 5/2/1999 14:4:51 Pacific Standard Time Pacific Daylight Time;
1> whenCreated: 5/2/1999 14:4:51 Pacific Standard Time Pacific Daylight Time;
1> msExchHideFromAddressLists: FALSE;
1> homeMTA: CN=Microsoft MTA,CN=KINDC,CN=Servers,CN=First Administrative Group,
CN=Administrative Groups,CN=OR1,CN=Microsoft Exchange,CN=Services,
CN=Configuration,DC=pique,DC=extest,DC=microsoft,DC=com;
1> msExchHomeServerName: /o=OR1/ou=First Administrative Group/cn=Configuration/cn=Servers/cn=KINDC;
1> mailNickname: jdoe;
1> mDBUseDefaults: TRUE;
1> msExchMailboxSecurityDescriptor: <ldp: Binary blob>;
1> deliveryMechanism: 0;
1> msExchFBURL: http://pique.extest.microsoft.com/public/Public Folders/non_ipm_subtree
/SCHEDULE%252B FREE BUSY/EX%253A%252Fo=or1%252Fou=first administrative group
/USER-%252Fcn=Recipients%252Fcn=jdoe.EML;
Windows 2000 User - Mail-enabled Only
First Name: John
Last Name: Doe
User Logon Name: jdoe
Email address: jdoe@microsoft.com
>> Dn: CN=John Doe,CN=Users,DC=pique,DC=extest,DC=microsoft,DC=com
1> accountExpires: 9223372036854775807;
1> badPasswordTime: 0;
1> badPwdCount: 0;
1> codePage: 0;
1> cn: John Doe;
1> countryCode: 0;
1> displayName: John Doe;
1> mail: jdoe@microsoft.com;
1> givenName: John;
1> instanceType: 4;
1> lastLogoff: 0;
1> lastLogon: 0;
1> legacyExchangeDN: /o=or1/ou=First Administrative Group/cn=Recipients/cn=jdoe;
1> logonCount: 0;
1> distinguishedName: CN=John Doe,CN=Users,DC=pique,DC=extest,DC=microsoft,DC=com;
1> objectCategory: CN=Person,CN=Schema,CN=Configuration,DC=pique,DC=extest,DC=microsoft,DC=com;
4> objectClass: top; person; organizationalPerson; user;
1> objectGUID: f8aa1b8a-00d2-11d3-a9c5-00c04f68099e;
1> objectSid: S-15-323E04BE-1898D11E-2B3BE507-459;
1> primaryGroupID: 513;
2> proxyAddresses: X400:c=us;a= ;p=PIQUE;o=OR1;s=Doe;g=John;; SMTP:jdoe@microsoft.com;
1> pwdLastSet: 125701528249531250;
1> name: John Doe;
1> sAMAccountName: jdoe;
1> sAMAccountType: 805306368;
2> showInAddressBook: CN=All Users,CN=All Address Lists,CN=Address Lists Container,CN=OR1,
CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=pique,DC=extest,DC=microsoft,DC=com;
CN=Default Global Address List,CN=All Global Address Lists,
CN=Address Lists Container,CN=OR1,CN=Microsoft Exchange,CN=Services,
CN=Configuration,DC=pique,DC=extest,DC=microsoft,DC=com;
1> sn: Doe;
1> textEncodedORAddress: c=us;a= ;p=PIQUE;o=OR1;s=Doe;g=John;;
1> userAccountControl: 66048;
1> userPrincipalName: jdoe@pique.extest.microsoft.com;
1> uSNChanged: 6481;
1> uSNCreated: 6473;
1> whenChanged: 5/2/1999 14:7:48 Pacific Standard Time Pacific Daylight Time;
1> whenCreated: 5/2/1999 14:7:4 Pacific Standard Time Pacific Daylight Time;
1> msExchHideFromAddressLists: FALSE;
1> internetEncoding: 1310720;
1> mailNickname: jdoe;
1> targetAddress: SMTP:jdoe@microsoft.com;
1> msExchMailboxSecurityDescriptor: <ldp: Binary blob>;
1> msExchALObjectVersion: 52;
Windows 2000 Contact with No Target Address
First Name: John
Last Name: Doe
User Logon Name: jdoe
Exchange Server e-mail address: jdoe@microsoft.com
>>Dn: CN=John Doe,CN=Users,DC=pique,DC=extest,DC=microsoft,DC=com
1> cn: John Doe;
1> givenName: John;
1> instanceType: 4;
1> distinguishedName: CN=John Doe,CN=Users,DC=pique,DC=extest,DC=microsoft,DC=com;
1> objectCategory: CN=Person,CN=Schema,CN=Configuration,DC=pique,DC=extest,DC=microsoft,DC=com;
4> objectClass: top; person; organizationalPerson; contact;
1> objectGUID: a2d12e98-00d3-11d3-a9c5-00c04f68099e;
1> name: John Doe;
1> sn: Doe;
1> uSNChanged: 6491;
1> uSNCreated: 6491;
1> whenChanged: 5/2/1999 14:11:56 Pacific Standard Time Pacific Daylight Time;
1> whenCreated: 5/2/1999 14:11:56 Pacific Standard Time Pacific Daylight Time;
Windows 2000 Contact with Exchange Address Specified
First Name: John
Last Name: Doe
User Logon Name: jdoe
Exchange Server e-mail address: jdoe@microsoft.com
>> Dn: CN=John Doe,CN=Users,DC=pique,DC=extest,DC=microsoft,DC=com
1> cn: John Doe;
1> displayName: JohnDoe;
1> mail: jdoe@microsoft.com;
1> givenName: John;
1> instanceType: 4;
1> legacyExchangeDN: /o=or1/ou=First Administrative Group/cn=Recipients/cn=JohnDoe;
1> distinguishedName: CN=John Doe,CN=Users,DC=pique,DC=extest,DC=microsoft,DC=com;
1> objectCategory: CN=Person,CN=Schema,CN=Configuration,DC=pique,DC=extest,DC=microsoft,DC=com;
4> objectClass: top; person; organizationalPerson; contact;
1> objectGUID: 6388a3bd-00d3-11d3-a9c5-00c04f68099e;
2> proxyAddresses: X400:c=us;a= ;p=PIQUE;o=OR1;s=Doe;g=John;; SMTP:jdoe@microsoft.com;
1> name: John Doe;
1> showInAddressBook: CN=Default Global Address List,CN=All Global Address Lists,
CN=Address Lists Container,CN=OR1,CN=Microsoft Exchange,CN=Services,CN=Configuration,<BR/>
DC=pique,DC=extest,DC=microsoft,DC=com;
1> sn: Doe;
1> textEncodedORAddress: c=us;a= ;p=PIQUE;o=OR1;s=Doe;g=John;;
1> uSNChanged: 6486;
1> uSNCreated: 6486;
1> whenChanged: 5/2/1999 14:10:10 Pacific Standard Time Pacific Daylight Time;
1> whenCreated: 5/2/1999 14:10:10 Pacific Standard Time Pacific Daylight Time;
1> msExchHideFromAddressLists: FALSE;
1> mailNickname: JohnDoe;
1> targetAddress: SMTP:jdoe@microsoft.com;
Important In the
Windows 2000 Contact with Exchange Address Specified contact type, the following two attributes have to be added to ensure that an attachment is sent correctly to the contact:
1> InternetEncoding: 1310720
1> mAPIRecipient: False