I believe that Parallels is causing a network problem when I try to upload photos for Substack. I had uninstalled it, but it created huge problems and I had an awful time getting my machine to boot at all. I reinstalled a new copy of Monterey after I wiped my HD, but I have a feeling there are residual bits lying around. It's the only reason I can think why I'd keep getting a "network connection error" for the substack site.