subject: Resolving Ost Synchronization Error: 80030070-501-80030070-560 [print this page] Being the exact replica of mailbox stored on Exchange Server computer, Microsoft Outlook Offline Storage Folder (OST) allows complete access of your e-mails, calendar entries, contacts, etc. on your local computer. The folder offers offline data access and allows downloading new messages after successful synchronization with server. However, OST file corruption, Exchange Server failure, mailbox deletion, profile modification, and similar reasons can eventually make OST inaccessible. The reason is that in such cases, OST cannot be converted to a readable PST. Thus, to facilitate the operation, you need to take aid of a third-party Convert OST to PST tool.
If a failure occurs, you can view the synchronization logs and analyze the cause. In MS Outlook 2002 and earlier, these logs are recorded in 'Deleted Items' folder. To illustrate these type of failures, let's consider the following synchronization log that might occur when trying to connect to Exchange Server and thus synchronize the OST file:
Beginning offline folder file integrity check.
Performing initial synchronization.
Synchronizer Version 11.0.5604
Synchronizing Mailbox 'mailbox_name'
Synchronizing Hierarchy
Synchronizing server changes in folder 'Drafts'
Downloading from server 'server_name'
Synchronizing local changes in folder 'Inbox'
Uploading to server 'server_name'
1 item(s) moved to online folder 'D'
Downloading from server 'server_name'
Error synchronizing folder
[80030070-501-80030070-560]
The client operation failed.
Where, 'mailbox_name' and 'server_name' respectively can be replaced with the names of user mailbox and Exchange Server computer.
Cause
The above error is generally observed due to insufficient disk space available for OST file. Another reason can be corruption of OST file that either prevents or causes issues when you try to connect to Exchange Server.
Solution
Make sure that you have sufficient disk space available for your OST files. If this doesn't work, you can recreate the OST file after determining that a good backup of e-mails is available.
