OwnCloud eats files in the most insidious manner, <i>and this is known to the devs</i>, who in the past have suggested that the workaround is to use another sync application. <i>DO NOT USE OWNCLOUD</i> if you value your data!! We discovered OwnCloud eating files after about three months of office paranoia, beginning to wonder if it was an inside job of a disgruntled employee. Turns out it was an inside job of incompetent software.<p>Also OwnCloud DOES NOT support &quot;delta sync&quot; (i.e. uploading file chunks when tiny portions of files are changed, instead of, for example, needing to upload the ENTIRE gigabytes-large file when only 10KB have changed). The core devs have kicked the can down the road at every opportunity (for example take a look at the huge BountySource bug for that issue, it&#x27;s like USD 1200 or something, in addition to the issue being locked to contributors because of all the +1s). This means for any use case involving large files (e.g. TrueCrypt&#x2F;VeraCrypt volumes), you will quickly find yourself in a messy situation of continually uploading gigabytes of data. It was painful to experience even on a gigabit LAN.