# PsychoPy encountered an unhandled internal error

**URL:** <https://discourse.psychopy.org/t/psychopy-encountered-an-unhandled-internal-error/18957>\
**Category:** Builder\
**Created:** [December 13, 2020, 4:16pm UTC](https://discourse.psychopy.org/t/psychopy-encountered-an-unhandled-internal-error/18957 "2020-12-13T16:16:25Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![Francesco\_Pupillo1](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.psychopy.org/francesco_pupillo1/32/12908_2.png) [@Francesco\_Pupillo1](https://discourse.psychopy.org/u/Francesco_Pupillo1)\
**Post date:** [December 13, 2020, 4:16pm UTC](https://discourse.psychopy.org/t/psychopy-encountered-an-unhandled-internal-error/18957/1 "2020-12-13T16:16:25Z")

</div>

**OS** : Ubuntu 20.04.1  
**PsychoPy version** : v2020.2.10  
\*\*Standard Standalone? \*\* y  
**What are you trying to achieve?:**  
I am trying to run an experiment created on another machine with ubuntu 18.04 on a PC with ubuntu 20.04

**What did you try to make it work?:**  
I tried to change the psychopy version on experiment settings

**What specifically went wrong when you tried that?:** Nothing changed  
Traceback (most recent call last):  
File “/usr/local/lib/python3.8/dist-packages/psychopy/app/runner/runner.py”, line 731, in onItemSelected  
self.updateAlerts()  
File “/usr/local/lib/python3.8/dist-packages/psychopy/app/runner/runner.py”, line 752, in updateAlerts  
self.currentExperiment.integrityCheck()  
File “/usr/local/lib/python3.8/dist-packages/psychopy/experiment/\_experiment.py”, line 154, in integrityCheck  
self.flow.integrityCheck()  
File “/usr/local/lib/python3.8/dist-packages/psychopy/experiment/flow.py”, line 124, in integrityCheck  
entry.integrityCheck()  
File “/usr/local/lib/python3.8/dist-packages/psychopy/experiment/routine.py”, line 52, in integrityCheck  
entry.integrityCheck()  
File “/usr/local/lib/python3.8/dist-packages/psychopy/experiment/components/\_base.py”, line 669, in integrityCheck  
win = alerttools.TestWin(self.exp)  
File “/usr/local/lib/python3.8/dist-packages/psychopy/alerts/alerttools.py”, line 17, in **init**  
self.monitor = self.exp.settings.monitor  
File “/usr/local/lib/python3.8/dist-packages/psychopy/experiment/components/settings/ **init**.py”, line 901, in monitor  
self.\_monitor = Monitor(self.params[‘Monitor’].val)  
File “/usr/local/lib/python3.8/dist-packages/psychopy/monitors/calibTools.py”, line 126, in **init**  
self.\_loadAll()  
File “/usr/local/lib/python3.8/dist-packages/psychopy/monitors/calibTools.py”, line 445, in \_loadAll  
self.calibs = json\_tricks.load(thisFile, ignore\_comments=False,  
File “/usr/local/lib/python3.8/dist-packages/json\_tricks/nonp.py”, line 266, in load  
return loads(string, preserve\_order=preserve\_order, ignore\_comments=ignore\_comments, decompression=decompression,  
File “/usr/local/lib/python3.8/dist-packages/json\_tricks/nonp.py”, line 236, in loads  
return json\_loads(string, object\_pairs\_hook=hook, \*\*jsonkwargs)  
File “/usr/lib/python3.8/json/ **init**.py”, line 370, in loads  
return cls(\*\*kw).decode(s)  
File “/usr/lib/python3.8/json/decoder.py”, line 337, in decode  
obj, end = self.raw\_decode(s, idx=\_w(s, 0).end())  
File “/usr/lib/python3.8/json/decoder.py”, line 355, in raw\_decode  
raise JSONDecodeError(“Expecting value”, s, err.value) from None  
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)