Everything was deleted after the update
I opened DIM to install recently purchased items, and then a program update popped up. I clicked OK, and after reinstalling the main program, I found that all my content libraries were deleted. Now I have to re-download everything. What did I do wrong to cause this? I don't want this to happen every time I update.

Comments
Check to see if the libraris are still on your computer and just need to be relinked. It is unlikely that they were deleted since erasing a big bit of data takes a fairly long time. So, go to Daz Studio > Preferences > Content Manager and relink the locations where everything should be before you consider downloading again.
At first, I thought so too, but after checking that the path was the same as before, I found that the hard drive, which was almost completely full, was almost empty (several hundred gigabytes less). Only then did I realize that it had been deleted.
DIM didn't do that, there is nothing in the installation process that will touch your installed content. I woudl suspect either a hardware issue or possibly soem kind of aberrant security software.
Thanks for chiming in, I am in the middle of a update as we speak, and I was worried...