This is simply to do with the binary being compressed in the wrong format for Big Sur.Ī simple solution is to open the 'Terminal.app' on your Mac then install homebrew to decompress the binary to the correct format. I have checked 7 (so far) out of 23 games Steam flagged as incompatible with Catalina (I presume they have not added Big Sur yet) & found 5 work ok (as you suggested), so wonder if you can help with advice on this problem also? The second message is: os error 4294956470 & tells me I must contact Steam. Originally posted by I have just installed Mac OS Big Sur & am getting 2 messages when I try to play Syberia 3, one tells me I am not authorised to use the app, this I have checked & the permissions are all correct.
