It is possible that (anti-virus) security software is causing the problem. Try to disable security software temporarily to see if that makes a difference.

Thank You for the quick response. Unfortunately I can't disabled any security software at this enterprise PC. Such software / backgroud services completley under control by the IT deparment. (As I wrote, Google chrome at the same PC works correct. MS Edge, too.)

Installed now a second Firefox - Windows 32-bit, English (US), Firefox Setup 118.0.2.exe - and with this version the Apache http download worked! Sound like a problem with my "Enterprise Version" 115.3.1esr (64-bit).

FWIW downloading with 115.3.1esr on Windows 10 gives me the correct sha256 checksum for httpd-2.4.58.tar.bz2.

Try changing secure DNS over HTTPS (DoH) to "Off" or "Increased Protection" and in Connection Settings change "Use system proxy settings" to "No proxy".

Changed both, no success. I did a "od -h" on the wrong and on the correct file, there You can see the "extra" load at the end.

wrong with extra "0000" at the end 34434520 ce02 74bb b054 b4c6 5746 7218 a217 b351 34434540 472a ac1c 98f6 c9b7 4159 add8 ff0f b98b 34434560 9c22 4828 a212 b76f 0000 0000 0000 0000 34434600 0000 0000 0000 0000 0000 0000 0000 0000

34435000 "httpd-2.4.58.tar_vcv4.bz2_od_h" 467861L, 22793519B

correct with just 1 time "0000" at the end 34434520 ce02 74bb b054 b4c6 5746 7218 a217 b351 34434540 472a ac1c 98f6 c9b7 4159 add8 ff0f b98b 34434560 9c22 4828 a212 b76f 0000 34434571 "httpd-2.4.58.tar_firefox32bit.bz2_od_h" 467859L, 22793453B