Ubuntu 16.04: heirloom-mailx is replaced by s-nail

As of Ubuntu 16.04, the heirloom-mailx package is a transitional package for s-nail.

Not realising this, I was having trouble with mailx not recognising the /etc/nail.rc file I’d copied from a working Ubuntu 15.10 server. As it turns out, the global config file path for s-nail is /etc/s-nail.rc. I found this out quickly by using strings to find the text '.rc' in the mailx binary: strings /usr/bin/mailx | grep '\.rc' (thanks to jpollard for this tip).

Beware of the MiniNT registry key

As of Windows 10 Version 1511, ReFS isn’t available by default as an option when formatting drives that aren’t part of a Storage Space. It’s easy, however, to enable this functionality by adding a DWORD named AllowRefsFormatOverNonmirrorVolume under the Registry key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\MiniNT (an example guide can be found here).

Unfortunately, the presence of MiniNT Registry key causes various Windows components to think they’re running in the Windows Preinstallation Environment. Significantly, the presence of the key breaks the Event Viewer – attempt to open any log and you’ll be greeted with the following very unhelpful error message:

Event Viewer cannot open the event log or custom view. Verify that Event Log service is running or query is too long. The request is not supported (50)

If this weren’t enough, apparently Windows PowerShell remoting will stop working, too.

TL;DR: Delete HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\MiniNT as soon as you’re done formatting your drive with ReFS.