Thank you SO MUCH for these instructions. I have now been able to rebuild my sync location and can again get to my databases on my iPhone! What a nightmare when I suddenly was unable to sync to my phone, and it started asking for an encryption key–and I couldn’t find an encryption key. Don’t even remember ever entering one, and I put all my passwords in a safe app. But your instructions guided me through a “painless” process (although time consuming, waiting for the data to upload again from my Macbook). I have copied your instructions and have saved them, where else, in DevonThink! 
The same thing happened to me yesterday and I rebuilt the whole syncing (again, it happens about once a year and I have used iCloud and Dropbox, my current sync location). As it was embarrassing this time - had a customer meeting without the files that I changed the day before on my 2nd Mac… not realizing that sync was broken - I was looking for a better solution than my sync nuke and pave. This brought me here. So at least I learn that I am not the only one and that something somewhere is broken sometimes. I am on DT 3.5.1 on both Macs. Actually I “solved” it the usual way, it works (until it doesn’t), so it’s a +1 for any effort of DEVONtechnologies to fix this.
My Dropbox sync stopped working suddenly months ago. DT tech worked at length and could not solve it. We concluded it was an isolated Dropbox issue as nobody else had the problem. I switched to CloudMe and have been fine ever since.
Since then you are about the 5th person on this Forum to report similar “isolated” issues.
So clearly there is an ongoing random issue where for unknown reasons Dropbox sync to DT3 simply stops working after being well established for a while.
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+1. This has happened twice to me this year (a Dropbox sync store corruption; or at least, syncing stopped). DT support were fabulous but couldn’t point to a reason. I ended up creating new sync stores; uploading DBs afresh, loosing a few hours like the other posters. I’m still with Dropbox at present since my life revolves around it, so fingers this will not happen too often.
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I have raised this with support but there have been a number of timeout delays and syncing issues in recent days. This is now a regular occurance and I am wondering if others have the same experience with a Timeout. (NSURLErrorDomain -1001) problem.
For me it isnt a sync issue with Dropbox. It is whenever I send a file to DT. No cloud syncing involved because it all on the same MacBook
Overview:
I the following error on sync: Error Domain=NSURLErrorDomain Code=-1001 “The request timed out.”
The solution appear to leave the Sync application in the foreground on a strong internet connection for the entire sync process.
My issue is that I am running a 200 mbps connection so I have a strong connection.
The only difference is actually that older versions didn’t use a time out to interrupt the stalled Dropbox SDK, meaning that in the past the sync was stalled until DEVONthink was restarted.
+1 same here, going through the motions every couple of months.
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Well, I am joining the list of users with the same issue! 
First time happened a month ago, and it happened again today. Really frustrating as it takes hours to re-sync our 10GB Database across 3 sites. ARGHH!!
Surely, if we are all having the same issue, someone must know why!!
I was never able to create a solid repro, nor trace down what was going on. For me, the clincher was that it failed silently, with no error, leaving you to notice that sync was broken.
I switched to a combination of local (Bonjour) sync and iCloud. I find iCloud slow compared to Dropbox, but so far its been reliable, but I also use Bonjour sync on local network which is (unsurprisingly) very fast.
Thanks!
Not sure I can use iCloud, we have 3 different users that need to sync this DB.
You cannot use iCloud for cross-account syncing. You can only sync with the same Apple ID on each machine.
For me, the clincher was that it failed silently, with no error, leaving you to notice that sync was broken.
Correct. There is no logged data there is an issue and the issue is not only sporadic, it’s not reproducible at will.
This really is a deal breaker for us. I have just sent the last 5 hours resyncing data etc. If this is a “known” problem, then Drop Box support should probably be pulled altogether - or at least have clear disclaimer that it’s not 100% supported. Now I have to find an alternative. Sad!
Just adding another report of a similar issue here, so that I can follow along if anything develops.
I am using Dropbox to sync with DT3, and noticed that things were out of whack a few weeks ago. I cleaned out the sync store at that time and got everything working fine again, but now the sync is totally stopped. My database is quite large so it’s a pain to have to clean out each time…
I am having this problem yet again. Typical - just when I needed the sync to work. I have an iMac, a mabcookpro, and my iPhone/ipad
I see the last successful sync which is on all devices was the 8th July. I discover today that the files I added on each device have not synced, so I have three different versions of what should be a single global inbox. This has happened before, and I’m so frustrated. Why does this keep happening. I haven’t changed any settings - not do I get an error message! I’m so frustrated
Welcome @philippefraser
Hold the Option key and choose Help > Report bug to start a support ticket. Thanks.
You are not alone. It is an ongoing problem with Dropbox sync.
I was similarly frustrated and switched to CloudMe - it has been flawless for months since I made that switch.
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Great, then i just have to pay for 3 different cloud storage providers 
Or find one that works reliably and consolidate everything there.
That isn’t an option. There isn’t a single one that works reliably (dropbox does except with DT). Hence I am forced to use icloud (some apps i use only use icloud), dropbox for everything else… and cloudme just for DT
Since DT doesn’t support icloud and dropbox, it puts me in an awkward situation.
DT does support iCloud. iCloud is just not a very fast or reliable service 
Not even with Apple’s own services.
1 Like