How are you setting the password change?  is it via a security policy?  if so, does the user has his notes ID embedded in his mail file?

If this is via a policy, does it work for any usrs?

Need more information to truobleshoot this issue.

We use ID vault so ID gets download during the setup and you have local copy of the ID in the workstation.

Once user updates the password it will synchronized up to ID vault.  

I have verified it does work for other users..

at in order to see whether security policy has been applied.?

There is adminp request to "Change User Password in Domino Directory" but I don't see for "Change HTTP Password in Domino Directory"

There are no error messages..

I've run into this before where one of my customers was running local replicas of db's on their machine. They changed their password and then promptly shut down Notes. The problem with that is that Notes wasn't given time to send the "hey I changed my password" information to AdminP. It wasn't until the next morning when they connected again that it actually sent that info and then AdminP did it's thing.

Are you enforcing that update setting or is it something the user might have changed?

We are enforcing users to update password every 6 months and it's set to Update Internet Password When Notes Client Password Changes.  

How are you applying that setting in your policy though? Is it possible that your user has that unchecked for their ID?

You may be setting it but it might not be locked down.

We had the same issue, Do you have a mail cluster ?apparently  policies only work if the user is connected his/her Home Mail server which can be found in the person document ( Mail Server field ) once this was corrected this started working for us, but this is a pain as we have 4 mail servers in our cluster. Here's a document i created for our helpdesk .. Hope this helps

When a Lotus Notes Client changes the password(Notes ID Password) it should  sync the password with the IDVault and also generate a Adminp request to change the HTTP Password used for Sametime, iNotes Quickr and also Connections.
This synchronization is set by the Domino Client Policies for the Lotus Notes Client, If this does not happen do the following to make sure the settings are correct.

Open Contacts 
Go to Advanced>Connections make sure there is a connection document for the above “Home Mail server”  if not create one
Open Contacts 
Go to Advanced>Locations>Online>Servers (Verify the mail server is correct)
Open Contacts 
Go to Advanced>Locations>Online> Open the document in edit mode by clicking the “EDIT” then go to Actions>Advanced>Set Update flag > Click “Yes” then Save & Close
*Note you will not see Advanced options when you go to Actions if you and not in edit mode
While you are in contacts press down CTRL+SHIFT and then go to View>Go TO scroll down to “$Policies view” chose the listed policies and delete them. this will update at restart if the settings are correct
Restart The Lotus Notes Client (password Sync will only happen when the client restarts)
Check the $Policies View to see if the deleted policies are back (they should be back if the procedure worked,if not set the update flag again and restart client)
Check with the Domino Admins to see if the AdminP request has come through to the server 

**Adminp Request can be found in "all requests by action" > "Change HTTP Password in Domino Directory" under particular users name