Darn, thanks

@Sarah Ochs: Yes, of course... Sorry, I forgot that not everyone runs Windows... :-|

@Sarah Ochs A MAC won't have Windows Registry. Someone will have to come up with a similar work-around for MAC. If it is possible, it probably involves editing a plist file for adobe to set navpanes = 0. See Adobe link on changing settings below.

https://www.adobe.com/devnet-docs/acrobatetk/tools/AdminGuide_Mac/predeployment_configuration_advanced.html

Kjell-Ove, could you please assist with your suggestion? I have a Mac, btw, and 1) I copied and pasted the following into a Text Edit (.txt) file:

Windows Registry Editor Version 5.00

[HKEY_CLASSES_ROOT\Acrobat.Document.11\shell\Open\command]
@="\"C:\\Program Files (x86)\\Adobe\\Acrobat 11.0\\Acrobat\\Acrobat.exe\" /A \"navpanes=0\" \"%1\""

2) I named the file No_Bookmarks.reg and then 3) I saved the file to my desktop. I then 4) opened the file, both directly from my desktop and then from a Finder window. Both yielded the same result, which was nothing. (My computer just opened the .txt file with the Text Edit app.)
What am I missing?
Thanks

When it stopped working for me, I simply re-ran the reg file, and the bookmarks pane was gone again...

That registry setting only worked in some cases, and it stopped working after a period of time, so that is not a solution.

I agree that Abobe should add an easy option to enable or disable this, but you can easily fix it by importing the attached registry file. (Unfortunately, this site didn't accept upluad og a .REG file. What you can do is: a) Open Notepad b) Copy the text below and paste into the Notepad c) Save the text in a file and make the file extension .REG (e.g., "No_bookmarks_for_me.reg") d) In the File Explorer, find the file you just saved, double-click it and confirm that you want to allow the file to make changes to your computer. Providing you run Adobe Acrobat Professional version 11; here is the text you need to copy (after the dash, including the empty row):
-
Windows Registry Editor Version 5.00

[HKEY_CLASSES_ROOT\Acrobat.Document.11\shell\Open\command]
@="\"C:\\Program Files (x86)\\Adobe\\Acrobat 11.0\\Acrobat\\Acrobat.exe\" /A \"navpanes=0\" \"%1\""

I echo the comments below. Having the unnecessary and unused bookmarks window pop up on documents is very annoying. Having the tools menu pop up is also annoying. I do use the tools but would rather use a single click to bring up that menu when I need it than use a click to close it on every document that I don't. None of the fixes suggested below work for all documents. PLEASE fix this! Why would Adobe be forcing users to put up with this? It's just SILLY!

I tried the registry setting changes described below.
It works for opening new files.
But, if I Open Recent Files from within Acrobat, it doesn't work.
So, there still isn't a perfect solution.

I've wanted this "feature" gone for years. It is so annoying to have to close the bookmarks panel every time I open a PDF because it wastes so much space on the screen and provides zero information. By default, the bookmarks panel should be closed. Or, give an option to have the default be bookmarks panel closed.

None of the PDF's I open have any bookmarks. Still it's showing as standard and taking up screen space and decrease the page size. No settings to permanently hide it. Really annoying! This is so basic for the user experience. I just can't understand why this option is removed from previous versions.

I only made an account here to comment about this most infuriating setting. I dont know how many hours i have trawled the internet trying to find how to turn bookmarks off to be told it cant. 😭 Come on Adobe, this is an elementary issue - why is it taking so long for a fix?

None of this works in Acrobat DC latest build. AND the bookmarks is even more annoying as it is 3 times as wide. I cannot even see the page tucked away on the left until I close the bookmarks. Please let us set a preference to open files with it closed!!!

Having bookmarks automatically appear when opening new PDFs is an INCREDIBLY annoying feature. And individually having to select bookmarks not showing up is not an option. Adobe absolutely needs to create a settings option that lets you automatically hide the bookmarks panel when opening new PDFs.

Adobe: Please for the love of all that's holy, add this setting ASAP!

Oh my goodness having to close the bookmarks pane every single time I open a document is maddening. Seriously maddening. I'm in and out of them all day long. Total waste of time. How there isn't a system setting to change this is beyond me. Maybe if it were free, I'd be less apt to complain, but I pay for Acrobat Pro, so I'm paying to be infuriated while I use the software. No bueno.

This is infuriating that this is the default to show this ****. First I had to find how to hide the Tools panel taking up 1/3rd of the screen which auto shows up which I NEVER use. Then I had to work out how to stop the Comments panel from auto opening taking up another 1/3rd of the screen which I NEVER use. Now I'm trying to stop the Bookmarks panel from auto-opening taking again, another 1/3rd of the fking screen!!!!! Why do these useless panels auto-show by default??? I'm out! Off to find another PDF viewer.

PS Austin's comment is 100% and made me laugh (and cry)

"I open dozens of PDFs every day and having that giant panel take up a third of my viewing screen every time makes me want to smash my keyboard"

Hi! I found a couple of registry hacks that fixed this for me. Here they are:
1:
I named this file "RegEdit for AcrobatPro11-NoBookmarksAtOpen - 1, Original, before edit.reg", but of course the filename can be anything with a .reg extension. (Create 2 text files containing the text below and save it as .reg files. Then double click these to make Windows update the registry and viola!
-------------
Windows Registry Editor Version 5.00

[HKEY_CLASSES_ROOT\Acrobat.Document.11\shell\Open\command]
@="\"C:\\Program Files (x86)\\Adobe\\Acrobat 11.0\\Acrobat\\Acrobat.exe\" \"%1\""
--------------------------------------------------
2: I named this file "!RegEdit for AcrobatPro11-NoBookmarksAtOpen - 2, NavPanes=0.reg"
---------
Windows Registry Editor Version 5.00

[HKEY_CLASSES_ROOT\Acrobat.Document.11\shell\Open\command]
@="\"C:\\Program Files (x86)\\Adobe\\Acrobat 11.0\\Acrobat\\Acrobat.exe\" /A \"navpanes=0\" \"%1\""
------------------

Hope this helps you :-)

This is basically my only complaint about Acrobat and it is truly infuriating to me. I made an account just to comment on this. I open dozens of PDFs every day and having that giant panel take up a third of my viewing screen every time makes me want to smash my keyboard. There are a LOT of forums on various sites about this, people will usually say "it's a document property, Adobe can't do anything about it", but there's no reason a viewer can't be setup to overrule a document property for the user's experience. It's not even disabling the bookmarks, we're literally just talking about having the panel collapsed as a default.

So happy to find this fix. My first regedit - super easy.
Jack's regedit and John Barrow's instructions just saved me so much pointless clicking. Thanks!

Very annoying to open a PDF to a page which is not the first page of the PDF.