All doors and windows are wired, right now I have a GE nx8 I think.
Years ago I set a code for it, never really used the alarm, and lost code.
There is no way to reset it to factory specs, and yes I called them.

What is a good stand alone alarm that can use my home cell phone to call me if it goes off?
Do not want a company.

Yank the old box, and slap in a Honeywell Vista 20P instead.

Add a 6160RF keypad, and you can use any of Honeywell's wireless sensors, switches and remote keyfobs.

For remote monitoring, connect your Vista 20P to an EyezOn Envisalink EVL-4EZ Internet Interface Module - It'll automatically send you texts or email messages just a few seconds after any alarm event. It also allows you to arm or disarm the system with your smartphone, and monitor the system's status (i.e., which doors or windows have been recently opened).

The EVL-4EZ doesn't require any monitoring service - It sends alarm messages directly to your smartphone - for free.

It uses any available ethernet jack on your cable modem or router to connect to the internet - no cell modems or land lines required.

Thanks, I'll check it out.

How easy is it to wire that in to my existing wires?

I've had my Vista 20p for almost 25 years.  I just bought the 6160RF and eyezon system to add to the system.  Hoping to install it this week.

All the zones / switches are going to wire up the same. should be straight forward.

The hardest part might be setting up the Vista panel and configuring it... I'm not an expert on those panels, but you'll probably have to configure it through it's keypad.

I can almost guarantee you there is a way to reset your existing panel... there is always a way to totally reset it and start over... sometimes it means sending it back to the manufacuter to do it... but it might not be worth bothering for 50-60 bucks.

Yes, it is configured through the keypad.

There are a lot of settings to configure, so it's somewhat tedious.

However, there are some excellent youtube videos, and the Honeywell installation manual can be downloaded for free from various sources on the net.

I have the Honeywell and I think for a hard wired system it is the way to go. The house is hardwired while the detached garage and the shed further back are wireless. Love the system.
Mine is just set up with cell phone service only. I do have it monitored.

You can reset the factory settings on the NX-8 line.  The company isn't GE now, it's called Interlogix.  And they have three versions of the CADDX line that I know of: NX-8, NX-8V2, NX-8E.  The metal enclosure should have markings, or the board itself should that tells you which you have.

Page-17 of the Installation Manual shows how to reset the NX-8V2 to factory defaults.
https://static.interlogix.com/library/I-NX8V2-IM%20REV%20H%20Installation%20Manual.pdf

ETA: I re-read and see you lost the code.  I've heard it can be reset by direct cable connection, but haven't done that before.  I'm sure you've tried, but the default code is 9713.  There's only 10,000 possibilities unless the 6-digit code was enabled. :)

If you can get your NX-8 working again, Alarm Lab makes a stand-alone internet autodialer that'll work with it.

Basically, it connects to your security system's alarm siren output, and sends you text messages whenever the alarm sounds.

It doesn't give you the status monitoring or control abilities of the EyezOn unit, but it works with virtually any security system.

I installed and programmed the Honeywell 6160RF & the Eyezon module today.  It was fairly easy.  I installed the Eyezon app on both our phones and get notifications almost instantly (a few seconds.)  We can also arm and disarm the system via smartphone, pad or computer now.  I have not gotten the text and email notifications to work yet.  Text & email notifications working great now.
I even set up Alexa skill that allows us to arm and disarm the system by voice.

I just ordered a Honeywell Ademco 5834-4 Four-Button Wireless Key Remote and plan to hook it up to the Vista 20 via the 6160RF.