Error 0x8004102A in Outlook when syncing mail using the Hotmail connector (Error 1133)

I've recently switched one of my main email accounts over to the new Outlook.com which is excellent! On my main PC, I'm running Outlook 2010 and I've installed the Hotmail Connector For Outlook to give me more Exchange-like syncing experience rather than just simple POP mail.  Now if I read or delete an email on my PC, it syncs that change back to Outlook.com which then syncs it to my phone, etc.

Anyway, this setup has been working fine for a few weeks but for the last few days, I was getting an error from Outlook every time it tried to send/receive.  It was error 0x8004102A.  It would look like this...

“Task ‘<Hotmail account>’ reported error (0x8004102A) : ‘Error with Send/Receive’.” 

This indicates an error trying to sync items between the local Outlook mailbox on your Hotmail/Live/Outlook.com .  To get some more details, lets take a look at the sync log.

In Outlook, go to the area in the lower left were you see Mail, Calendar, Contacts, etc. and click the item called "Folder List".  This shows you ALL of the folders in your mailbox, even the usually hidden system folders.  Now look in your mailbox folder structure for a folder called "Sync Issues". This should contain several Sync Logs.  Check out the most recent one and scroll down until you see some errors.

In my case, I saw an error that looked something like this...


10:50:19 Synchronizing server changes in folder 'Deleted Items'
10:50:19 Error Synchronizing Message
               Error: 1133
               Server Command: CHANGE
 10:50:19 Server Id: 18F8A5F5-50A5-11E0-A9A0-00215AD6A70A
 10:50:19 Error with Send/Receive.

Basically it was trying to change(sync) something in the Deleted Items folder but it was having a problem doing so. This is indicated by the Error: 1133.  

I tried deleting everything in the deleted items folders both in my local Outlook as well as in Outlook.com but that didn't help.  Something was corrupt in my local mailbox.

The next step was to delete my cached local mailbox (the .OST file) and let Outlook rebuild a fresh copy.

If you are running Windows 7 or Windows 8, you can just enter this path into your command line and it will take you to the proper folder or you can just browse to this location...

%localappdata%\microsoft\outlook

Here you will find a file that looks like MyEmailAccountName.OST .  Close Outlook and then delete or rename this file.  It will wipe out your local cached copy of your mailbox.  Now launch Outlook again and it will download a fresh copy of all of your folders and messages from Hotmail/Live/Outlook.com and you shouldn't have the error any longer. It worked for me!  Note : it make take several minutes to download all of your email again, depending on the size of your mailbox and the speed of your connection.

Update: Since finding this fix and publishing this post, I've had to repeat this process a few times over the past few months.  It seems to me that the issue is probably caused by something like deleting an email from my phone and then maybe deleting it again from my local Outlook program before it's had a chance to sync with the server.  So my phone has already told Outlook.com to delete the message, so it should be gone. But then the Outlook program tries to delete the same message, can't find it because its already gone, then throws up this error message.