Data-loss warning

Always quit Palm Desktop 6.x before you shut down or restart your PC. If you fail to do this, it may cause data loss. See, for example, this forum thread. Can it also cause data corruption? I have no idea.

Slow synchronization

The first time you sync a data-filled Palm OS device with a new computer, it may take hours. Please be patient. Future HotSync operations will likely be much quicker.

Note

You'll probably have to start HotSync Manager manually. Once you install Palm Desktop, it'll be on your Start menu.

How to sync a Palm OS device with a 64-bit PC

You have choices. You can choose the Bluetooth method, the Wi-Fi method, the XP Mode method, the Linux method, the serial method, or the USB method. Maybe try the Bluetooth method first. If it doesn't work, post a new question, or try another method.

Bluetooth method

This might be simplest. You can sync using Bluetooth. For help, try a Google search for [ palm os bluetooth sync ].

64-bit Bluetooth drivers are included with Windows.

If your computer doesn't include a Bluetooth chip, you may need to buy a Bluetooth adapter.

This method should work, though I don't guarantee it.

In my experience, the Bluetooth method seems to work. Bluetooth doesn't seem quite as reliable as the Aceeca driver, but Bluetooth seems to be perhaps four times as fast.

If you have problems, see here.

Wi-Fi method

You may be able to buy and install some hardware in order to upgrade your Treo to support Wi-Fi. If you do this, then you can probably use Wi-Fi to sync. For help, try a Google search for [ treo wi-fi ].

This method may work, though I don't guarantee it.

XP Mode method

If you have access to a computer running Windows 7 Professional, Enterprise, or Ultimate, you can probably use Windows XP Mode to sync. Forward your USB port to XP Mode, install Palm Desktop and HotSync Manager in XP Mode, then sync. (Source.) See also this forum thread.

I don't think that XP Mode is supported in Windows 8 or any later Windows version.

This method should work — though I don't guarantee it — on any supported operating system.

Linux method

Modern Linux distributions still ship with a preinstalled Palm OS driver nowadays, just as they have for a couple of decades. It works fine on 64-bit computers. You may view the source code if you wish.

Install Ubuntu or another good Linux distribution. You can install Linux inside VirtualBox (plus its Extension Pack); then you can forward your USB port to the virtual machine. If you install Linux directly onto your computer, back up your data first.

Now, use Ubuntu Software Center or another package-management tool to download the jpilot package.

Finally, start J-Pilot.

If you're good with Linux, this method should work, though I don't guarantee it.

Serial method

You'll need a serial HotSync cable for your Palm OS device. You'll probably also need a USB-to-serial adapter. You may need to buy these things.

This method may work, though I don't guarantee it.

USB method

Aceeca Limited, in New Zealand, have released a 64-bit Windows USB driver for Palm OS synchronization. They've written that non-customers are free to use it, that they provide no support to non-customers, and that they accept no liability if it causes problems.

You can get it from their driver download page. Installation instructions are inside the Zip file.

I followed the instructions. They worked fine. Afterwards, Windows told me: "USB device not recognized. ❧ The last USB device you connected to this computer malfunctioned, and Windows does not recognize it." I ignored the message. You should too.

Press the HotSync button.

The Aceeca driver may be extremely slow. See here. I've started the process of synchronizing the 60 MB of data from my Treo 700p to a Windows 10 machine. After two hours, some progress has been made, but it's still not yet done. I think my AddressDB file may contain some corruption, and so I don't know whether or not the Address Book conduit will ever finish synchronizing. I may post a separate question about this. Or I might use Wireshark to watch the bits going over the USB cable and to see if any progress is actually still happening.

It may speed things up if you disable unneeded conduits; there's more information in this thread.

If you need more help

If any of the above methods doesn't work for you, please post a new question.

Sources

My sources for this answer include part of a Wikipedia article, plus other sources.