When you create a Linux virtual machine on Azure, the portal asks you to download a small file ending in .pem. Many beginners click through, forget where it went, and later find they can't get into their own server. This post explains what that file is, how it works, and …

If You've Ever Run git push and Been Greeted With This...

git@github.com: Permission denied (publickey).
fatal: Could not read from remote repository.

...you know the particular flavor of dread it brings. The good news: this error is almost always fixable in a few minutes once you know where …