For a long time I’ve been looking for the perfect utility to synchronize files an documents between the three PC’s I use on a daily basis. For home entertainment I have a Media Hub that’s built on Windows Media Center, I use my laptop around the house or if I’m working out of the office, and finally there’s my work PC that’s the mainstay of my day to day development work. Among these three I like to keep a copy of my music library on each for easy listening, and have various personal and work documents mirrored between my laptop and workstation.

Up to this point I’ve performed this file synchronization through adhoc solutions that have included one or more combinations of FTP, batch-files/scripts, VPN tunnels with shared drives, and an off the shelf solution such as Vice-Versa. These have all worked to a point, but the robustness and automation capabilities have all been lacking. However, around a month ago, quite by chance, I found a less well known member of the Windows Live Family - Folder Share.

Folder Share uses a web-based interface coupled with a lightweight satellite application that runs on multiple PCs, or devices as Folder Share terms them. Using the interface a user first creates a “Library” by choosing a folder from a device running the satellite program and then assigning it a name. After the library is created other devices can be added to the library, after which all contents and changes will be replicated between devices.

In the above screenshot “Sync My Folders” is the option used to create libraries to be synchronized between devices belonging to a single users, and “Share With Friends” is an alternative sharing mode. It works much like the main synchronization mode but the creator may assign access rights to users based on their Folder Share login (e.g. email address). In this way it’s possibly to create a Library where all changes and additions will be replicated to other users while preventing them from altering the state of the library. One really nice feature is that, firewall permitting, it’s possible to browse online devices and retrieve files over the web. These files aren’t limited to items belonging to a library either, though one downside is you may only retrieve individual files like this and not entire folders.

One negative point about creating libraries is there’s no way to exclude files or certain sub-folders. At the moment if I wish to have a “My Documents” library then I cannot have a separate “My Music” library as libraries cannot be nested. I understand the reasoning for this but it’s unfortunate because a) I only want to sync music to my Media Center, and b) with the combination of MP3’s and years of documents I exceed the 10,000 file limit that Folder Share places on a library. I’ve worked around this by syncing My Music and then creating a new sub-folder for all my documents that I wish to keep synced, but this isn’t an ideal solution. I’d much rather be able to exclude “My Music” and have it as a separate library.

While it’s a sad indication of the “Web 2.0″ world in general, and Windows Live services in particular, one of the things that impressed me most about the web interface of Folder Share was how it worked flawlessly across all browsers, including my preferred choice of Opera. Unfortunately I suspect that when (if?) Folder Share sees future versions this may become a casualty of the march to add more browser-candy - which would be a shame because the existing interface already works very well.

The satellite application must be run on all devices that wish to participate in folder sharing or synchronization. It lives in the tray and is quite a basic application, infact it even states it’s basic in the title and the status bar! No Advanced mode exists though, and there are few options - account settings, proxy setup and some rudimentary options for throttling bandwidth by reducing the maximum number of active transfers.

This simple interface is indicative of my main complaint about Folder Share - a lack of options and configurability. For example; if a remote machine has deleted a file from a library then it won’t be deleted on other devices, but will instead be moved to a Trash folder. This is great in theory, but there is no way to set a quota for the amount of trash, nor to disable it or instead use the standard Recycling Bin. If you do some heavy directory reorganization you can find gigs of space vanishing to be used for Folder Share’s trash. The satellite GUI is functional but does need some reworking. The information listed is sparse and confusing and it’s difficult to tell whether the files listed are pending updates or completed updates.

When a device is first added to a library Folder Share builds a list of required changes. If a file does not exist in a location then it’s added to the list of files to be synchronized and a temporary file with a .p2p extension is created. The temporary file acts as a proxy until the original is downloaded, if the user attempts to open or run it the actual file is bumped straight to the top of Folder Share’s queue and opened after it’s downloaded. It’s a simple feature, but very welcome if you’re synchronizing a lot of data. Folder Share also offers an “On Demand” option for devices in a library where this behaviour is then the default. This is great for cases where you may not need all of the files that are stored on a remote device but wish to have them available.

Should there be a conflict between files then the name of the newest file is appended with the name of the device where the modification occurred, e.g. “Expenses.xls” becomes “Expenses on WorkPC.xls”. This is one of my less liked features of Folder Share, ideally there would be a conflict resolution pane in the Web Interface where I can choose which copy should be the default, or replace both with a merged version I’ve created. The detection of changed files also seems to be solely based on date and not a check of the actual contents. Most of the time this isn’t much of a problem, but it does lead to redundant copying when files have been shifted around locally.

So how does Folder Share perform? After using it on a daily basis for the past month I have to give it a big thumbs up. It’s easily the best method of synchronizing files between remote PCs that I’ve come across. It’s robust, reliable, and virtually invisible to the user. Everytime a potentially sticky situation has been encountered such as a lack of drive space or a missing folder it’s taken the sensible approach and asked how to proceed. It’s handled everything I’ve thrown at it with flying colors, including two weeks I spent in our UK office where I installed the client app on my temporary machine and the next morning had all my music and documents waiting for me

I do hope that future versions will address some of the problems I’ve found, but Folder Share seems to have become somewhat stagnant compared to other Windows Live services. It’s clear from the website that Microsoft acquired the technology as part of an acquisition so it may just be in a transition stage. However there are many similarities between Folder Share and features that were removed from Vista,or that are being touted for Office. I really hope that Folder Share is going to remain as a separate tool rather than having its technology absorbed into other applications.