Hello again.
Months ago I installed Zorin on my computer but I didn't check the integrity of the ISO file (I'm quite new in computer building and GNU-Linux, sorry). Well, now I've compared the numbers of the checksums and they don't match at all.
The version I Installed was Zorin-OS-16-Core-64-bit-r1.iso. The actual one is the r4, I think. Do checksums change between older and newer versions? If not, what could happen if I installed a corrupted ISO file?
Yes, checksums can change when a new revision or version is released. Your r1.iso has a different checksum than the r4.iso would have.
If you have had no trouble in the past several months, you are likely just fine.
Checksum's like SHA256 are generated from the file content. The r1 and r4 releases are effectively different versions of Z16 Core, so the iso file is different and its corresponding file checksum is different.
If, as we always recommend, you checked the SHA256 for your downloaded r1 iso file, before installing it, then you are OK.
If you need the SHA256 for Z16 Core r1, let me know and I will find it for you.