I recently started using a new computer, so that meant installing Kaspersky (Internet Security) as a fresh install with all default settings.
Yesterday, Kaspesky Software Updater wanted to install an “update” to Dropbox. I allowed it, and it wiped out my previous version of Dropbox and reinstalled a fresh version. That meant that it deleted the Dropbox directory in my user profile with all local files (Dropbox cloud files are unaffected), and needed to be reconfigured (Selective Sync) and re-download many GB of files from the cloud.
I recall having this happen a year or two ago on a previous computer. At the time, I sent some angry messages to Dropbox, but it turned out that the issue was Kaspersky. Dropbox automatically checks for updates and will install updates *without wiping out all synced files*. It’s actually not possible to prevent Dropbox from doing this. In general, that’s worked fine. I’ve never had an issue with Dropbox going wonky after it updates itself. The issue seems to be that Kaspersky is checking for updates in a beta channel or some other unnecessary and problematic way.
My solution now (and I believe this is what I did with the previous computer) is to just turn off the Software Updater. Pretty much all software already includes a utility to check for updates, so this Kaspersky feature is practically useless anyway, and it’s actually damaging and disruptive in the particular case of Dropbox. My recommendation to Kaspersky developers is to drop this feature, as it’s only been a negative experience for me as a user.