issue with WriteXLS: The Perl script 'WriteXLSX.pl' failed to run successfully

I have code which used to work OK but now always failed.
issue is WriteXLS. Example below.

WriteXLS(starwars,ExcelFileName="tableau.filename"starwars.xlsx,Encoding = "UTF-8")

Error is

No such file or directory\mikec\AppData\Local\Temp\RtmpiOHBFb/WriteXLS/1.csv
The Perl script 'WriteXLSX.pl' failed to run successfully.

I have looked at output of tempdir(). No issue I can see. It is as if WriteXLS is truncating the first directory elements

[1] "C:\\Users\\mikec\\AppData\\Local\\Temp\\RtmpiOHBFb"

What I have found is an error on opening the library:

In system(cmd, intern = intern, wait = wait | intern, show.output.on.console = wait,  :
  running command 'C:\WINDOWS\system32\cmd.exe /c ftype perl' had status 2

There are many R packages that can write xlsx files, you chose one based on Perl; therefore you would need to follow the instructions here https://cran.r-project.org/web/packages/WriteXLS/INSTALL

my advice is, don't use this library unless it's doing somethings its competitors can't do for you.

Yes. It is from some of my earliest code.
Since then I have standardised on write_xlsx

But I figured I should work it out anyway
The workaround with the "perl =" below works - so I will leave it there:

WriteXLS(starwars,ExcelFileName="starwars.xlsx",Encoding = "UTF-8", perl = "C:/Perl64/bin/perl")