SNAP stopped openning anything after atmoscpheric correction of Sentinel-2 for 10m resolution

Good evenyning, everyone.
I have the following problem. It occured after I run atmospheric correction for Sentinel-2 for 10m resolution. There were no errors. The process seemed to be completed. And the programm slowed down significantly. So I restarted it, and then restarted the computer. When I reopened Snap and tried to open corrected data. It did not work at all. I tried to open original data. It did not work as well.
I got the following error message in all the cases:
java.lang.NoClassDefFoundError: Could not initialize class org.esa.snap.core.datamodel.Product
at org.esa.s2tbx.dataio.s2.ortho.Sentinel2OrthoProductReader.buildMosaicProduct(
at org.esa.s2tbx.dataio.s2.Sentinel2ProductReader.readProductNodesImpl(
at org.esa.snap.core.dataio.AbstractProductReader.readProductNodes(
at org.esa.s2tbx.dataio.s2.ortho.Sentinel2OrthoProductReaderProxy.readProductNodes(
at org.esa.snap.core.dataio.ProductIO.readProduct(
at org.openide.util.RequestProcessor$
at org.netbeans.modules.openide.util.GlobalLookup.execute(
at org.openide.util.lookup.Lookups.executeWith(
[catch] at org.openide.util.RequestProcessor$

Is there any way to fix this or I will have to uninstall SNAP and install everyting again?
Thank you in advance.

java.lang.NoClassDefFoundError This error is very general of many causes, But I didn’t find any related in STEP FORM search,

This could be the solution, But more details about

What AC. did you implement and How?

What are the properties of your machine?

This really sounds as if your installation is corrupted. Please try to uninstall and reinstall SNAP.
Please also make sure that you enable the option “Remove all SNAP user data”.

System: Windows 7, 64-bit, Intel®-Core™i3-4160CPU@3.60GHz 3.60GHz, installed memory 4Gb

Model of computer:HP ProDesk 400 G2 MT (TMP DP)
First, I downloded the scen from earthexplorer, I unzipped it, opened SNAP, opened Sentinel-2 product choosing MTD_MSIL1C.xml file thus all bands were loaded to SNAP. Then I started to perform atmospheric correction like following Optical-Thematic Land Processing - Sen2cor processor - Sen2cor255. Then in the window that opend I chose first 60m resolution, when the processing finished I chose 20 m, then when it finished I chose 10 m. Then I had to restart the programm because its response become very slow. I wanted to open corrected 10 m first. In corresponding folder I got rather large .database.h5 file. I tried to open it in SNAP but I got the error I posted. Then I tried to open 20 m (jp2 file for each corrected band). I got the same error. I was not able to open or import anything.
I guess there might be something going wrong when processing 10m resolution. Or it might be caused by updates I allowed SNAP to install. I need to process 7 scenes and now it looks like almost impossible task.

The processor and RAM of your machine are still low to meet the processing data in SNAP, from my previous experience using similar machine’s properties I couldn’t do anything.

The processor i7 or up is good and also the RAM, 16GB is good start, in the future you could upgrade it.

But the failing of open, it could be cameback to the reason is mentioned by @marpet

I reinstalled SNAP and it worked properly only for 60 m resolution this time. When I tried to get 20 m, I got memory error. Thus, I guess I will try another computer. This seems to be the major issue.