Naming Files

NEVER use slashes (or colons) in filenames. MacOS may get confused.

Attempting to use a slash character in a filename runs the risk that it is interpreted as a directory reference.

For example:

/Applications/Utilities is the name of the Utilities directory, located inside the Applications directory

You can use numbers and most symbols. You can’t include a colon (:) or start the name with a period (.). Some apps may not allow you to use a slash (/) in a filename.

from:

Rename files, folders, and disks on Mac - Apple Support

JoAnneMaggio wrote:

Got the latest version of Illustrator that I subscribe to yearly. It acts way differently than last version. First I name a file PG2/3 and save. It renames itself 3.ai. Can't find files like I named ANYWHERE!

Spotlight by default searches your entire hard drive: Command Spacebar

for your third party software—

If in doubt refer to the developers website; Support/Help/FAQ/known issues/compatibility /updates

Contact a third-party vendor - Apple Support

ref

Adobe Illustrator Learn & Support

Adobe Help Center