This question has materialized after this strange interaction: multiple instances of macOS, installed on different hard drives on the same machine, share settings.

Example: I have this MBR 16”, 2020. On the internal hard drive I was running Catalina. Let’s call that (A). On an external SSD I had installed another copy of Catalina. We will call this (B).

While using (B), When adding folders in the “do not search” setting for Spotlight, whatever folders I would add would be added in the “do not search” list of (A).

When connecting to a certain WiFi only on (B), the WiFi info was added to (A) as well, including password.

Unless unmounting the internal drive or encrypting both of them, they would communicate for some reason when you would expect two separate entities of macOS on two different drives to not share configuration files.

Why does this happen?

LE: Corrected Spotify into Spotlight


1 Answer 1


Wi-Fi: Wi-Fi passwords are stored in NVRAM/PRAM if you have ever used Wi-Fi in Recovery mode or for an installation. So both macOS installations can use that.

The output from the Terminal command nvram preferred-networks will include the names of WiFi networks - the passwords are encrypted.

Spotlight: Spotlight indexes and settings are specific to the disk volume. These are stored in the .Spotlight-V100 hidden folder. So preventing Spotlight from searching particular locations is an attribute of the volume and so would be used by both installations.

  • Comments are not for extended discussion; this conversation has been moved to chat.
    – bmike
    Jun 21, 2021 at 19:10

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .