> It looks as though you have installed from security.debian.org but now > it's not in your sources.list. If you add a line like > > deb http://security.debian.org/ buster/updates main contrib non-free > > then do "apt-get update", does that help the "apt-get build-dep"?
This seems to have fixed the issue. I added the line and updated&upgraded, now I have this: libtiff-dev: Installed: 4.1.0+git191117-2~deb10u1 Candidate: 4.1.0+git191117-2~deb10u1 Version table: *** 4.1.0+git191117-2~deb10u1 500 500 http://security.debian.org/debian-security stable/updates/main amd64 Packages 100 /var/lib/dpkg/status 4.0.10-4 500 500 http://ftp.uk.debian.org/debian stable/main amd64 Packages Thanks a lot! -- İ. Göktuğ Kayaalp / @cadadr / <https://www.gkayaalp.com/> pgp: 024C 30DD 597D 142B 49AC 40EB 465C D949 B101 2427