Whenever I click on an attachment link (like attached .html) to open the file in the default browser I get this error on Window 10
I do not have this issue with the regular Markdown editor, I can click and open the file in it, so this is definitely not a browser or the actual attachment issue.
It seems like the slashes in the file uri is the issue.
This desktop does not have direct internet access, but I am not sure why the internet access is a necessity here. The attachment is embedded/attached in the note, and is on the actual drive under the resources folder. This is not an external link to an external html website.
I am using Joplin 2.4.6 on Windows 10 The default browser is Edge
It is possible that windows checks the internet access when opening an HTML page... especially with Edge. Can you try to open this file with Firefox or another browser?
That cant be the issue because I can open the same attachment in Joplin when I use the regular Markdown viewer mode. And it opens with Edge (since it is the default) fine.