I missed the bit about you having overwritten your working DLL on first reading. Are you telling me that your "more than 15 years of continuous hard work" isn't backed up anywhere? But assuming you indeed have no way to recover this previously working DLL, there must be dozens of places online to download a copy. I hesitate to point you at any place to get precompiled binaries for Windows other than the software's trusted source, but [this one][1] is probably trustworthy. [1]: https://chocolatey.org/packages/sqlite/3.31.1