Sync protocol error message on HTC incredible droid cell phone

Here is one way you can get rid of the error and start getting your email messages again!

NOTE: Internet searches indicate that the error may be related to your phone’s internal memory filling up, so after you do this “fix” the issue may crop up again in the future.  You can try setting your email to retrieve less data with each message, but again, that might only work as a bandaid. The issue may also be related to old, bad mobile associations in activesync, but I haven’t been able to confirm this.  That being said..here is the way to get rid of old associations and reset the activesync association for your user (which will allow them to get email again without deleting and restoring the Exchange account:

There’s a tool for Microsoft Exchange called the MobileAdmin tool which, according to Microsoft “is designed for administrators who want to manage the process of remotely erasing lost, stolen, or otherwise compromised mobile devices.”

This tool can be downloaded here: Download details: Microsoft Exchange Server ActiveSync Web Administration Tool

Download and run the file on your Exchange Server to install the tool.  There are instructions on how to use the tool in the unzipped folder, but if all you’re looking for is a quick fix to the above then follow these steps:

1. Open Internet Explorer: https://localhost/MobileAdmin, sign in using the admin account for the Exchange Server
2. Once signed in, click on the Remote Wipe link, enter the username of the user whose phone is acting up and click the green arrow
3. You get a list of mobile phone associations.  In my case there were alot of old ones.
4. Delete them all and then have the user Re-Sync his phone.  A new association should appear after syncing.
   NOTE: This process will wipe out the Inbox and then redownload emails for whatever time period you selected.

Option 2: Delete the Exchange Account off the phone and re-add it.  This works for some people, but I know alot of users who aren’t comfortable performing such tasks themselves.  Also, doing so can mess up options and settings which the user has on their account,  so try the Admin tool if you can..it’s easy and remote!

Option 3: (Tested 7/28/2011) Reset the phone completely and add the Exchange account before any other account (ie gmail). To do this:

1. Take out battery.  Replace battery.
2. Hold down “Volume down” button and then press Power button…should boot to a configuration menu
3. Use Volume down button to highlight option Clear Storage, Power button to select this option. (Note: Once you do this you lose all third-party data.)

Someone on the thread linked below found that if exchange email was set up first, before any other, you don’t get the “protocol error”. 

If this doesn’t solve your problem or you want to lookup more current information, there’s a thread on this issue here.

Note: Exchange 2010 has this tool built-in