Subprocess.Popen() not working when reading file path from csv file

[herwin]

In the new code

print(prg)

will give:

Output:
C:\\Program Files\\Google\\Chrome\\Application\\chrome.exe

so the correct value is read into the variable.

No it is not correct. The path should be: "C:\Program Files\Google\Chrome\Application\chrome.exe", so without the double backlashes.
The backslash has a special meaning in Python. So to assign a string literal with backslashes you have to double the backslash to make clear you really mean one backslash.

>>> prg = 'C:\\Program Files\\Google\\Chrome\\Application\\chrome.exe'
>>> print(prg)
C:\Program Files\Google\Chrome\Application\chrome.exe

So "prg" will contain only single backslashes.
Nowadays a more popular way to assign such a variable is to assign a raw string by putting an "r" before the string literal.

>>> prg = r'C:\Program Files\Google\Chrome\Application\chrome.exe'
>>> print(prg)
C:\Program Files\Google\Chrome\Application\chrome.exe

So make sure you get rid of the double backslashes.

Thank you for your response and suggestions.

I have tried with the single and double backslashes in the csv file. The error message stays the same in both cases.

How do I read the values from the csv file into the prg variable as a raw string?