User getting locked out

I got a user whos account getting locked out several times a day.   He saying happens when he trying to put his password into iphone and ipad.  He swears he puts a correct password.

In the event log I see event 675
Pre-authentication failed:
       User Name:      username
       User ID:            domain\rwyman
       Service Name:      krbtgt/domain
       Pre-Authentication Type:      0x2
       Failure Code:      0x12
       Client Address:
and the next event 680:
 Logon account:      username
 Source Workstation:      hislaptop
 Error Code:      0xC0000234

I'm confused why itis coming from his laptop as a source if he is trying from iphone/ipad. Also I see other users have the same events but this one only getting locked out...

Please advice.
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Randy DownsConnect With a Mentor OWNERCommented:
try this -
Download and install the Account Lockout and Management Tools, this will help you pinpoint the location of the failed auth attempts: 
Tiras25Author Commented:
Do I install it on the Domain Controller or the user's workstation?
Randy DownsConnect With a Mentor OWNERCommented:
Looks like you can install it whereever is convenient. I'd install it on your workstation.

•Supported Operating Systems:Windows 2000;Windows NT;Windows Server 2003

Caution: Do not use this tool on servers that host network applications or services. Also, you should not use ALockout.dll on Exchange servers, because it may prevent the Exchange store from starting.
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AmitConnect With a Mentor IT ArchitectCommented:
Account lockout tool is good, but tracing the root cause with till tool is not easy. Better option, is just to append 1 like if username is user change it to user1. That should fix the issue. There will be no impact on user desktop etc.
every1isevil2Connect With a Mentor Commented:
ipods and ipads if a failed auth tries 10 times with in seconds.  check audit logs for failed atempts.  
JavedtariqConnect With a Mentor Commented:
The Best and easy fix for this is reset his local profile on the laptop. or any other accounts he is using on that laptop computer.
Ask him to log back in again and this will create a new local profile. This should resolve the issue for you as this has worked for me previously
Tiras25Author Commented:
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