I downloaded the Linux ARM64 build from this page (last link on the page): https://www.princexml.com/latest/

I installed it on my raspberry pi 4B, which has Broadcom BCM2711, Quad core Cortex-A72 (ARM v8) 64-bit SoC @ 1.5GHz

I installed it like this:

$ sudo ./install.sh /usr/local

Now when I run "prince" i get the following error:

$ prince
/usr/local/bin/prince: 3: exec: /usr/local//lib/prince/bin/prince: Exec format error

Why is this failing?

Can you check the binary is as expected:

$ file /usr/local/lib/prince/bin/prince
prince: ELF 64-bit LSB shared object, ARM aarch64, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-aarch64.so.1, for GNU/Linux 3.7.0, BuildID[sha1]=8149395620255e93867338be42a72e6cb11a6889, stripped

thanks for the quick response. running "file /usr/local/lib/prince/bin/prince" produces a somewhat different result than what you posted. it says "LSB pie executable" instead of "LSB shared object".

$ file /usr/local/lib/prince/bin/prince
/usr/local/lib/prince/bin/prince: ELF 64-bit LSB pie executable, ARM aarch64, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-aarch64.so.1, for GNU/Linux 3.7.0, BuildID[sha1]=8149395620255e93867338be42a72e6cb11a6889, stripped

i figured it out. although my Raspberry has a 64 bit processor, it was running a 32 bit OS. i installed 64 bit OS and now prince is installed and responding as expected.