I did succeed in installation of Niresh Catalina and everything is fine except wifi. But when I re-install it again, it showed me the following error:
 
	An error occurred while running scripts from the packages OSInstall.postscript.pkg
 
	My question is why this error happened?
 
	My Dell is Latituted E74040, Core i7-4200 2.2GHz, 8GB, 500 GB SSD
 
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