Dock disappearing on my Mac mini running macOS Sequoia 15.3

Try deleting Dock preferences.

You can do it in Terminal with these two commands:

defaults delete com.apple.dock
killall Dock

For good measure, you may also restart your mac (or log out and back in).

FWIW, this is not a general problem in 15.2 or 12, it's problem specific to your mac - and more likely, to just your own account.

If deleting Dock preferences doesn't fix it (which I think it will), we will need to know more. Please run Etrecheck and post its full report here. Use the "additional text" button and paste the report into the text box.

companys wrote:

Thanks Luis ! Yes I will try that but i am skeptic it will work...

I already did several rebooting under 15.2 and 15.3 -> it did not change anything.

Restart alone would not, but clearing a possibly corrupted preference file may.

In all logic, I would expect the behavior of the dock to be similar whether it is located in the bottom or on the side. It never disappears when set on the side ... only when it is in the bottom.

I will revert back to let you know for sure.

Thanks!!

PRP_53 raises a good point, if you just can't see the Dock at the bottom.

My interpretation, though, was that the Dock at the bottom automatically hides (but does appear when move the cursor there).

Anyway, "Automatically hide and show the Dock" should not appear greyed out, so definitely something is amiss.

I bet that if you (only as a test) create a new user and log in as that user, the Dock will work there just fine - thus reaffirming my supposition that the problem is only with your account, and deleting the preferences is the right thing to do.

Follow the advise from @ Luis S - First

From your user byline " Mac mini, macOS 15.3 "

Obviously this machine would be using an External Display

Is there an chance the Display is using a Resolution that is Too Large

I know, using a M2 Mac Mini via HDMI ( Sequoia 15.3 ) to my Smart TV

I had to decrease the Resolution indoor to get the Dock to appear at the Bottom of the TV Screen

Moving the Dock to the side of the Screen was OK

companys wrote:

I forgot to ask...you requested that I run Etrecheck ... it is known as malware. Is there another tool I can use that I can download from the Apple store?

Background Etrecheck Application 

At one time there was an  Etrecheck Application available on the Apple Apps Store.

Due to certain constrains place upon the Developer by APPLE, the developer chose to remove it from the Store and make is available Directly from them.

This specific application is well known,  on these Forums,  as a Go To for trouble shooting and avoiding all the question / answer and question / answer to finally get the issue pinned down.

It is also known and reported by Reliable Sources that,  sometimes APPLE SUPPORT has invoked using this same Developer Distributed Version of Etrecheck application to trouble shot computer issues 

Lastly - should you decide to use and post the Report now or at a later time, we are willing to have a very close look and offer some insights 

companys wrote:

I forgot to ask...you requested that I run Etrecheck ... it is known as malware. Is there another tool I can use that I can download from the Apple store?

To reinforce what PRP_53 and dialabrain have said already: NO, Etrecheck in not malware. It is a diagnostic tool by a respected member of this community, and frequent contributor, and used in these forums every day. All it does is producing a report so users here have enough information to help.

companys wrote:

I forgot to ask...you requested that I run Etrecheck ... it is known as malware. Is there another tool I can use that I can download from the Apple store?

In a act of good faith

If this Etrecheck application was indeed malware

I for one, would not let it any where near my 3 computers

Refer to " Etrecheck Report " for my M2 Mac Mini

EDITED - Self

EtreCheck is hardly malware. It's the most recommended diagnostic tool here on ASC. No one would recommend it if it was malware.

Sorry Luis ,I could not resist butting in on the Etrecheck as Malware

PRP_53 wrote:

Sorry Luis ,I could not resist butting in on the Etrecheck as Malware

No problem. Thank you for stepping in.