I actually tried Allway Sync a few months ago and I liked it except for one thing. It won't use Volume Shadow Copy to be able to sync locked files. Their FAQ even says that this is a deliberate decision. I suppose this is a desired thing if you're doing a true 2-way sync, but if you're doing a one-way sync for backup purposes, I prefer that it be able to use Shadow Copy to get locked files.
I also looked at GoodSync (http://www.goodsync.com) and it seems to work great including Shadow Copy. I was all set to actually buy this one, and then somehow (I forget exactly how) I found out about this free alternative...
Free File Sync (http://freefilesync.sourceforge.net). I found out about this just about 2 weeks ago, and finally took a look at it yesterday. t does do Shadow Copy for locked files, but it doesn't handle versioning of old files quite the way I'd like compared to what I saw both in Allway Sync and Goodsync. But I've just posted in their forum and we'll see where that goes. OH, and Free File Sync doesn't support backing up to cloud services, which of course is the subject of this article (but GoodSync does), but I'm only trying to back up to a local USB hard drive for now.
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