MATLAB: Can’t create a symbolic variable

errorMATLABmupadmexsymsymbolicsymsvariable

I am trying to create a new variable x so I run
syms x
Unfortunately, Matlab stays as 'busy' for around 5 minutes and then displays these messages
>> syms x
Error using mupadmex
Internal error with symbolic engine. Quit and restart MATLAB.
Error in symengine
Error in sym (line 189)
      symengine;
Error in sympref>implementedSymprefs (line 142)
 y = {'FourierParameters', sym([1,-1]), 'MuPAD', 'sym';...
Error in sympref (line 81)
iSymprefs = implementedSymprefs;
Error in syms (line 195)
calledFromBase = mupadmex('', 8);
Warning: Failed to initialize symbolic preferences.
> In syms (line 195) 
Error using mupadmex
Internal error with symbolic engine. Quit and restart MATLAB.
Error in sym>cell2ref (line 1303)
S = mupadmex(y);
Error in sym>tomupad (line 1241)
  S = cell2ref(numeric2cellstr(x));
Error in sym (line 215)
              S.s = tomupad(x);
Error in syms (line 197)
toDefine = sym(zeros(1, 0));
I have indeed tried restarting Matlab. I have also tried resetting my paths, and rehashing the toolbox cache. I have even reinstalled Matlab, yet the problem persists.
Any help?
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