Windows 10 user here. Whenever I try to open it from the Windows search, or even directly from the .exe, it doesn't open. I need a solution for this, as I use it to manage tons of my downloads, and I don't want to use any other software.

Hello,
Please send me the log file (e.g. via the private message on this forum).
You can find it here: %LOCALAPPDATA%\Softdeluxe\Free Download Manager\logs.

was you ever able to find a fix? having the same problem after hundreds of flawless downloads. Now it doesn't want to open in a window. I heard i wasn't FDM's fault, but file explorer. didn't help me though.

Hello,
Please try to:
1. Reboot your PC.
2. Install the latest version of FDM.
Let me know if the problem persist.