Adobe Acrobat Reader is *incredibly* slow & keeps hanging - AGAIN!!

The "not responding" hangs on heavier files usually come down to how the reader loads a big document. The general PDF tools I have tested tend to choke on a big document, so they freeze on open and then stutters when you move around the page.

If you just need to read and mark up without the hangs, there are a few solid alternatives people in here already mention. (Disclosure: one of them is mine, so flagging that up front.) I make Ncored, a PDF tool I built as a working architect because the big drawing sets kept stalling. It opens fast and stays smooth on scroll, zoom and pan, handles heavy 50-200 MB+ project sets, runs without a subscription, and is Windows and Mac (Apple Silicon). There is a 14 day free trial, no signup, nothing to enter, if you want to throw a file that normally hangs at it.
 

After MONTHS of misery opening Adobe files and waiting for them to load, hang or simply not respond, i changed over to Nitro and have never had an issue since. 

Try updating Adobe Reader, disabling protected mode  or reinstalling. Also, check for large PDFs or system resource issues.

Are you using the "comment" tool? Acrobat is not ideal for projects that involve a large number of comments.  For those, you may try using a different PDF reader. There are free alternatives if all you need to do is add comments.

Foxit also provides admx/adml GPO templates so you can set the default apps easily, as it used to be in the good old days of Windows 7, before whatever nightmare this is started, obscuring everything, making it nearly impossible for admins to lock systems into a standard setup that everyone could count on.  The goal, if I just interpret the end results, seems to be to reduce productivity and undermine worker comfort and confidence pretty much across the board, while preventing admins from addressing this outside of registry hacks, which won't hold still long enough to really solve anything.  I used to understand that OS's and software were built to increase productivity and ease of use. That clearly is not what drives things anymore.

Adobe must be trying to force everyone to update to pro. Message: "We are experiencing Acrobat Reader download site problems (for months) and are working to resolve the issue." One of the largest software companies in the world having "problems" with their download site for their only free product.

Solution in Windows 10/11:

Control Panel > Installed Programs > Adobe > Uninstall Everything

Delete all C:\ProgramData Adobe folders

Delete all C:\username\AppData\Local (or Roaming)\Adobe folder, and delete everything in the Temp directory in the Local folder (don't delete the temp directory itself, skip anything that is in use.

Check your scheduled tasks for anything Adobe, delete

Restart computer

Problem solved.

Then just use the Foxit reader, which does not update itself to look different constantly, unsettling non-tech-savvy users.  Does not upsell users with upgrades to the full Acrobat -- WHICH IT INSTALLS IN THE USER CONTEXT TO CIRCUMVENT THE NEED FOR ADMINISTRATOR CREDENTIALS ON YOUR WORK DOMAIN, AND THEN EXPIRES, AND STOPS WORKING REQUIRING I.T. TO STEP IN AND REMOVE IT AND REINSTALL.

Adobe is garbage, been getting worse for years, and only artists compelled to use it for work should be using it for anything anymore.

Oh, and you can still buy a perpetual license of Foxit for like $150 for the full PDF software, if you don't want the subscription version.  Adobe's actions with installing the full Acrobat in the user context should have provoked a full blown revolt against them.  I know none of us I.T. people appreciated that little slimy maneuver.  Totally shady.

See you in the funny papers.

I, like others, am considering deleting ADOBE altogther despite being a paid subscriber for years.  The lagging is painful. I cannot work efficiently at all andcauses stress, major loss of productivity therefore income. I cannot reach out to tech support to walk me through issues.  As solutions offered are mixed I believe direct tech support is waranted. 

We faced the same issue  until we disabled the "new Acrobat" via the "hamburger menu.

See reddit answer below from "IHopeYouStepOnALego ":

Acrobat is Painfully Slow. How do I fix that? : r/Adobe