# \[Solved\] Error launching application: ClassNotFoundException: null

**URL:** <https://forum.inductiveautomation.com/t/solved-error-launching-application-classnotfoundexception-null/40489>\
**Category:** Ignition\
**Tags:** vision, ignition80\
**Created:** [November 10, 2020, 2:47pm UTC](https://forum.inductiveautomation.com/t/solved-error-launching-application-classnotfoundexception-null/40489 "2020-11-10T14:47:47Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![bmeyers](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/bmeyers/32/37453_2.png) [@bmeyers](https://forum.inductiveautomation.com/u/bmeyers)\
**Post date:** [November 10, 2020, 2:47pm UTC](https://forum.inductiveautomation.com/t/solved-error-launching-application-classnotfoundexception-null/40489/1 "2020-11-10T14:47:47Z")

</div>

[launch\_error\_2020-11-10\_08-43-15.log](https://forum.inductiveautomation.com/uploads/short-url/3anQjwB9Ye6CiEi8OIxardAc3g.log) (31.2 KB)

Good morning,  
I am running a NEW installation of 8.0.14 on Windows7 64 bit. Initially the startup works fine but on the 2nd startup I get an error launching application and the attached launch error file is produced. Can someone take a look at the file and let me know what I am missing on the system?

Thanks for any info.

Found this link here... deleting the app and adding it again seems to have worked.

> [@ClassNotFoundException launching Designer](http://forum.inductiveautomation.com/t/classnotfoundexception-launching-designer/20908/14):
>
> Ok it looks like that particular gateway was set to be the Default application in settings. Could you try something for me? Open the Designer launcher and when you see the auto-launching screen select Cancel on the bottom. You will then see a screen similar to the one that I posted. Click on the manage button on the thee-dots button to the right of the name of the Ignition-LAPTOP-RLSQD170 Designer: [image] Delete the application. After doing this, re-add it by click the blue “Add Designer” butt…

---

<div class="post-metadata">

**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\
**Post date:** [November 10, 2020, 3:11pm UTC](https://forum.inductiveautomation.com/t/solved-error-launching-application-classnotfoundexception-null/40489/2 "2020-11-10T15:11:11Z")

</div>

Hmm, it’s nice that there is a workaround/fix for this, but I wonder what the root cause is…

@Kurt.Larson or @jcoffman did this ever get a ticket or get fixed?

---

<div class="post-metadata">

**Author:** ![jcoffman](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/jcoffman/32/6429_2.png) [@jcoffman](https://forum.inductiveautomation.com/u/jcoffman)\
**Post date:** [November 10, 2020, 4:04pm UTC](https://forum.inductiveautomation.com/t/solved-error-launching-application-classnotfoundexception-null/40489/3 "2020-11-10T16:04:48Z")

</div>

Hi @bmeyers,

I was hoping you could get me a copy of the designerlauncher.log file as well? should be in the `.ignition/clientlauncher-data` folder. specifically im looking for the launch command used when this failed. It should be at the same time as the log you provided. You could DM them to me so they aren’t posted publicly if you would like.

Im looking for something specific that a fix went in for recently as part of 8.1.

Thanks,  
Jonathan C