I’m quite confident that this question has been asked in any number of ways, but I’m going to ask it in my own way because I’m petrified of losing data as I move from one machine to another. Here is the gist of it: DevonThink 3 is set up on my iMac. I’d like to fully, absolutely, and 100% completely remove my database from this computer and onto an external hard drive so that I can reset the iMac to factory settings. I tried performing this action, but when I did so the documents within the database did not transfer (just the file names, etc.).
So, again, how do I move everything (all inclusive) from my iMac to an external hard drive?
Simply close the database (File > Close Database >), locate the database in Finder and then copy the whole database file (which should end with .dtSparse for encrypted and .dtBase2 for unencrypted databases) to you external drive. Be safe and copy it to a second drive too.
If you want to keep your preferences, scripts, etc., you might want to see this post.
Edit: just to add to what I wrote: if, of course, your database contains indexed (rather than imported) records, then those will not be included in the database file.
And because I’m that guy, I’ll point you* towards a thread on backups - but not without mentioning that the handbook also goes into the topic on page 19 (of the DEVONthink 3.8 Documentation).