The following operations are for use only in rare, specific situations and should not be used for general troubleshooting. In many cases, resetting will cause additional problems.

By default, the Zotero sync process merges data between the Zotero client and the Zotero server. In certain rare situations, you may prefer to overwrite all data on one side with data from the other side. The reset mode to use depends on your situation:

If the Zotero sync icon is spinning and you're trying to fix it, do not use the reset options. See Sync Queuing for more information.

If all of your desired data is on the Zotero server, use Restore from Server.

If all (or nearly all) of your desired data is on one computer, use Restore to/from Server.

If you've transferred a Zotero library to another computer using export/import or by copying a Zotero 1.0 data directory and have added new data on more than one computer, you can use Restore to/from Server + Manual Merge to combine your libraries without creating duplicates.

In all cases, make sure to first back up your Zotero library.

First, check your Zotero library on zotero.org to verify that it contains all of your data. To view your library, log in and then click the My Library tab.

Next, if you have Zotero's auto-sync enabled, open the Zotero preferences without opening the Zotero pane. Go to Firefox's Tools menu, select Add-ons, and select the Extensions tab. Select Zotero in the list that appears and click the Preferences button.

Once in the Zotero preferences, click the Sync pane and the Reset tab within that. Select “Restore from Zotero Server”, and then click the Reset button.

Start on the computer containing the Zotero data you want to keep, and make sure Firefox is closed (or auto-sync is disabled) on the other computers.

If you have auto-sync enabled, open the Zotero preferences without opening the Zotero pane. Go to Firefox's Tools menu, select Add-ons, and select the Extensions tab. Select Zotero in the list that appears and click the Preferences button. Once in the Zotero preferences, click the Sync pane and the Reset tab within that. Select “Restore to Zotero Server”, and then click the Reset button.

Next, on each other computer you want to sync, open Firefox and, using the same method as above, access the Zotero preferences without opening the Zotero pane. In the Zotero preferences on each computer, click the Sync pane and the Reset tab within that, select “Restore from Zotero Server”, and the click the Reset button.

Your data should now be fully in sync across all your computers.

If you have a combination of identical data and new data on multiple computers, you can do a “Restore to Zotero Server” on the computer with the most recent data and then manually save differing data on other computers.

On the other computers, if you have auto-sync enabled, first access the Zotero sync preferences without opening the Zotero pane. Go to Firefox's Tools menu, select Add-ons, and select the Extensions tab. Select Zotero in the list that appears, click the Preferences button, select the Sync pane, and make sure “Sync automatically” is not checked.

Next open Zotero and sort My Library in the middle column by clicking on Date Added. (If you don't see Date Added, click the square button to the right of the column header row and select it from the list.) Select the recently added items and export them to Zotero RDF. If you've added or modified notes attached to older items, you'll want to export those as well.

After exporting, open Zotero's Sync preferences, click the Reset tab, select “Restore from Zotero Server”, and click Reset. After restoring, import the RDF file(s) you export back in and sync normally with the server by clicking the green sync icon. The imported items will be synced to your other computers.

You will need to relink reimported items in any documents created with the word processor plugins.

Full Sync is for troubleshooting only and should generally be used only if a Zotero developer recommends its use. In some cases, performing a Full Sync can cause new problems, particularly with large databases.

A full sync ignores all sync history, pulling all data from the server and comparing it to all local data. If any of the same items are different, you'll see a conflict resolution dialog allowing you to choose which copy to keep.