Sending build to others breaks the program?

Hi. I've come across a strange problem I only find on mac. There is a project that can be built and spread on windows easily, but I also want to share the build with mac users.

Now, I have a mac and I can build the project with it. I can easily run the game after having built it. I can also zip it, unzip it and the unzipped game works. But when I zip it, send it through the internet in some way (a chat program or uploaded to and downloaded from my website) the app is broken when it's unzipped. Even the same computer can't run the game after it has downloaded it from some place. When I try to open it, it says the program is damaged and should be put in the bin. I can't for the life of me understand what happens with the zip file when it it is uploaded somewhere. Does anyone have any advice?

 

Actually, I just found out looking through other forum posts in here. The first answer to https://forum.unity.com/threads/iss...g-sur-os-from-unidentified-developer.1026697/ solved my problem