topic Re: Autocad 2020 Can't Load LISP files after restore in AutoCAD Forum

Autocad 2020 Can't Load LISP files after restore

wdj03 — Fri, 12 Sep 2025 22:44:14 GMT

Hi, I had an issue with my 2020 v47.0.0 install where it would crash on opening (Unhandled access violation). I restored to defaults, and was able to open again. Then I restored my customizations, all seemed well.

However, I then noticed that none of the lisp routines in my startup suite were loading. I get a message in the bottom of the dialog box that says "Unable to load ###.lsp file". This happens for all of my files, even something simple like this won't load

(defun c:HELLO () (princ "\nHello World.") (princ)

My lsp files are all in a trusted folder which is set as read only in file explorer. The folder is also set as an exception in Windows defender.

I tried loading manually on the command line (load "c:\path\filename.lsp") and I do not get any feedback on the command line.

Is there some way that i can see some more verbose logging to find out what the problem actually is? I'm guessing that my company IT did something to our security settings preventing scripts from running, but I have no idea how to trace out the problem.

Any ideas?

Re: Autocad 2020 Can't Load LISP files after restore

paullimapa — Sat, 13 Sep 2025 01:55:16 GMT

What happens when you enter the following lisp function at the command line:

(alert "Hello World.")

Make sure you're not starting AutoCAD in safemode:

https://www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/How-to-launch-an-AutoCAD-Product-without-any-plug-ins-or-add-ons.html?msockid=1ca5fb1884aa67493ce1eaf485c06636

Betreff: Autocad 2020 Can't Load LISP files after restore

cadffm — Sat, 13 Sep 2025 07:30:41 GMT

Hi,

they sould do a clean deinstall, update and reinstall, test, update

deinstall Acad

Update windows and .net framework

turn Anti virus and similar off

account with admin rights, yours prefered

Install autocad

Your win account with admin rights to start

Acad the first time.

(Don't migrate from older version or custom stuff).

Close Acad.

Start acad, send (alert"HelloWorld") into commandline.

Re: Autocad 2020 Can't Load LISP files after restore

wessj03 — Mon, 15 Sep 2025 17:59:41 GMT

I entered (alert"HelloWorld") to the command line and got no response at all.

I checked my shortcut to ensure there was nothing in it that was putting me in safe mode and there isn't.

However, I did elevate my account to be an administrator (we are able to do that temporarily for installs, driver upgrades, etc) and it looks like I am able to run lisp routines normally when I am set as an Admin. It's pretty tedious and inconvenient to have to elevate my account, so I'm hoping that there's a workaround for this.

Any ideas for where to start with that?

Re: Autocad 2020 Can't Load LISP files after restore

paullimapa — Mon, 15 Sep 2025 18:27:49 GMT

Any reason for your Windows account to not have local admin rights?

Re: Autocad 2020 Can't Load LISP files after restore

wessj03 — Mon, 15 Sep 2025 19:02:28 GMT

@paullimapa wrote:
Any reason for your Windows account to not have local admin rights?

Corporate IT. They put this policy in place about a year ago. If we want to install or update any software, we have to get on VPN, then use an app to elevate our rights. Sounds easy, but it's a slow tedious process.

What's confusing is that this policy has been in place for a while, but it only affected my Cad install in the last couple of weeks. If there is some specific security setting that I can tweak to make Autocad a trusted application or something then i could probably do that but it's hard to know where to start for this kind of thing

Re: Autocad 2020 Can't Load LISP files after restore

paullimapa — Mon, 15 Sep 2025 21:26:05 GMT

Perhaps something’s happened with your Windows profile. Test by requesting IT to create a new Windows profile on that computer for you to login and then try launching AutoCAD within that login.

Re: Autocad 2020 Can't Load LISP files after restore

pendean — Tue, 16 Sep 2025 19:07:41 GMT

@wdj03 Are you running AutoCad2020 on Windows11 by chance? I wonder if you're getting affected by this posted issue https://forums.autodesk.com/t5/announcements-and-meet-greet/share-autocad-amp-windows-11-security-update-admin-prompt-for/m-p/13791031