MSNP3 is the second released version of the Mobile Status Notification Protocol.
It was introduced officially in Client Version 2.0.0085.

It introduces the notification service commands:
* IMS

*No switchboard or dispatch commands were known to be introduced in this version*

It introduces the error codes:
* 131
* 217
* 800

*No commands were known to be removed in this version*

Known changes (from [MSNP2](msnp2.md)):
* XFR: Added a new parameter that is always 0. No use is known or documented.
* Added Passport Site IDs to URL (parameter 3).
* Initial profile: Added Passport intergration fields.
* Font information has been added to Switchboard MSGs.
* Multiple error-codes unimplemented in 1.x that were in the draft are now implemented in the Official Client.
  Examples include: 208, 215, 501, 604 (bizzarely enough), 715 and finally 913.
* Non-protocol: Client can now use non-hotmail domains in relevant places.
* Non-protocol: WebTV 2.5+ clients (example@webtv.net) can talk to other users (example@hotmail.com)
* More URL requests implemented (assumed)
* Clear-Text Password (CTP) authentication method discontinued.
* Entire content of initial email notification changed from
  `text/x-msmsgsemailnotification` to `application/x-msmsgsinitialemailnotification`,
  the format is likely different. Now includes unread email count. \[Examination needed\]
* Official Client: Changed form that URL uses to login drastically.
  New format is undocumented, but now has MD5 `creds` instead of the plain-text `passwd`.

Client-server communication example:
```
C: VER 1 MSNP3 MSNP2 CVR0
S: VER 1 MSNP3
C: INF 2
S: INF 2 MD5
C: USR 3 MD5 I example@hotmail.com
S: XFR 3 NS 10.0.0.5:1863 0
```
Client disconnects from server

Client opens a connection to 10.0.0.5:1863
```
C: VER 4 MSNP3 MSNP2 CVR0
S: VER 4 MSNP3
C: INF 5
S: INF 5 MD5
C: USR 6 MD5 I example@hotmail.com
S: USR 6 MDS S prefix
C: USR 7 MD5 S $md5(prefix + password)
S: USR 7 OK example@hotmail.com example%20user
S: MSG Hotmail Hotmail 367
MIME-Version: 1.0
Content-Type: text/x-msmsgsprofile; charset=UTF-8
LoginTime: 1726321960
EmailEnabled: 1
MemberIdHigh: 1
MemberIdLow: 2
lang_preference: 1033
PreferredEmail: example@hotmail.com
country: US
PostalCode: 
Gender: 
Kid: 0
Age: 
BDayPre: 
Birthday: 
Wallet: 
Flags: 1027
sid: 507
kv: 11
MSPAuth: AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA$$

C: SYN 8 5
S: SYN 8 5
C: CHG 9 NLN
S: CHG 9 NLN
C: IMS 10 OFF
S: IMS 10 0 OFF
C: IMS 11 ON
S: IMS 11 0 ON
C: OUT
```
Client disconnects from server
```
S: OUT
```
Server disconnects client