I want to change L1C to L2A in snap

I downloaded sentinel data using qgis from copernicus. And I installed version 2.9 sen2cor. When I input MTD_TL.xml, I got a message which is "java.lang.illegalStateException: The naming convention structure is invalid for input file 'C:\Downloads\L1C_T52SBB_A002288_20151130T022422_2015-11-30\MTD_TL.xml.
And I entered the other xml file. I got a message which is xml could not be read.

I want to make L2A files.
Is the way I download the files wrong? How can I make L2A?

sen2cor is not comatible with the data structure downloaded by the qgis plugin.
If you want to convert L1C data to L2A you have to download the products here: https://scihub.copernicus.eu/dhus/#/home


thanks ABraun I want to get NDVI image from sentinel 2 How to set polarisation?

polarization is related to radar data, but for NDVI you use optical data such as Sentinel-2
A tutorial is given here: https://www.youtube.com/watch?v=9Y_5Q-932mM