Options
Basic
On the Options tab there are a number of useful things you may wish to set.
Normally, when you send your bookmarks and passwords, you will overwrite the bookmarks/passwords on your server. If the bookmarks on the server contained any changes you wanted to keep and hadn't yet received then these will be lost. The 'Send safely' option prevents this by always carrying out a receive first using the 'Only synchronise ...' and 'Merge ..' options described below. So the bookmarks on the server are received and merged into your local bookmarks/passwords first, and then sent to the server. So the whole process is a lot safer. Merging can be a complicated process, so it is recommended that you also read the How to use SyncPlaces page for information on how best to use this option and what to avoid.
The 'Sort before Send' option allows you to automatically sort your bookmarks before they are sent to the Server. For this you need to separately install the SortPlaces extension.
The 'Encrypt JSON' option allows you to encrypt your bookmarks before sending and decrypt them on receiving using standard AES or the faster TEA encryption (TEA is the default). Note if you don't use the same password in two different browsers, or forget to turn this option on in one of them, then you will get a 'corrupt bookmarks' message. Because the extension does the encryption/decryption, the bookmarks will be stored in encrypted format on your server and so be unreadable. Note that encryption is a large overhead and so may significantly slow the transfer process.
If you have a lot of bookmarks it may take a long time to transfer them. So you could use the 'Compressed JSON' option, which will attempt to GZIP your bookmarks when sending them and GUNZIP them when receiving. So less data is transferred speeding up the whole process. My own bookmarks are transferred 6 times faster with this option, so it could make a big difference. NOTE: Remember that you must send your bookmarks in GZIP format first before receiving them or you will get a 'corrupt bookmarks' message. This option is not guaranteed to work for everyone, but it is safe to try.

With the two 'Only synchronise ...' options SyncPlaces will checksum your bookmarks/passwords each time you send or receive them. It will then only send them again if they have changed. Each time your bookmarks/passwords are sent a small checksum (.sha1) file is also sent. When receiving, this file is obtained first and the bookmarks/passwords on the server only received if they have changed. So with this option you only send and receive bookmarks/passwords when needed saving time and bandwidth. It is also highly recommended that you use this option when merging bookmarks in order to prevent local changes being overwritten before they are sent. Note that changing the server settings, restoring a backup, changing the folder to synchronise, and changing profiles may throw away the checksums, so the next send/receive will always do something. Older versions of SyncPlaces used checksum files with the extension '.ts' or '.hash' and these may now be safely deleted.
Normally the bookmarks in your local browser are replaced by the ones on the server when you click the 'Receive' button. Use the 'Merge bookmarks received' option to merge the server bookmarks with your local ones instead, so that you do not lose any new bookmarks or changes. Additional settings for this may be found on the Advanced tab. Also read the notes on How to use SyncPlaces to avoid unexpected changes.
Normally the 'Merge passwords received' option is turned on so that the passwords and password exceptions in your local browser are merged with the ones on the server when you click the 'Receive' button. Uncheck the 'Merge passwords received' option to overwrite the local passwords and exceptions with your server ones instead.
Automation
You can automate the send/receive process using the options on this tab:

The 'Sync automatically' option will silently synchronise your bookmarks whenever they change. To cater for multiple changes in short succession the synchronisation happens when there have been no further changes for 30 seconds (you can change this default delay to anything between 3 and 999 seconds). Setting the 'Sync automatically' option will automatically set the 'Send safely' option described above, so that each time it runs it will receive, merge and then send (but only if there's anything to do).
The 'Receive on startup' and 'Send on shutdown' options allow you to receive the latest bookmarks from the server when Firefox starts and sends them when you close Firefox. With the 'Send safely' option, when shutting down and starting up Firefox a receive, merge, and send will be performed.
The 'regular intervals' option allows you to automatically synchronise your bookmarks/passwords/exceptions at regular intervals, and is fairly self-explanatory. This option also needs a Firefox restart to begin working, but once running the interval can be dynamically changed or the automation stopped without having to restart again.
The 'set time' option allows you to Synchronise at a specific time - as long as Firefox is running at that time. Again, this option will automatically set and use the 'Send safely' option. Note that the actual time the synchronisation happens may be up to 5 minutes after the time you set.
Note: The Startup/Shutdown options will display a transfer window, whereas the option options will synchronise completely silently unless there is an error in which case a pop-up window will appear.
General
By default all your bookmarks are sent to and received from your server (and all of them are exported/imported). If you uncheck the 'Synchronise all ...' checkbox then you can use the 'Select folder ...' button to choose a single folder to synchronise on. In this case only the contents of this folder are sent to and received from your server. This may be useful if you wish to share only part of your bookmarks between browsers. When the pop-up window appears, highlight the folder you wish to synchronise on and click the OK button to accept this.
If you wish to override the default and use a folder with a different name, then use the 'Allow different name ...' option, and choose a folder of any name using the 'Select folder ...' button.
See How to use SyncPlaces for more information on using these options.
Note: This option also applies to the import and export XBEL options. But does not apply when you click 'Backup' or 'Restore', which is always a full backup/restore for safety. It also does not apply to the 'Send HTML' option, which always sends all of your bookmarks as HTML.
Note: The pop-up window that you select your folder from is 'live' so if you drag folders around this window it will affect your bookmarks.

The 'Status bar icon', 'Bookmarks menu' and 'Tools menu' options allow you to decide where SyncPlaces appears within Firefox, and the 'Select folder to backup to' option allows you to decide where the backup and transfer files are stored should you wish to move them from their default location (a 'syncplaces' folder within your Firefox profile).
