After some time without uploading I tried yesterday a batch. The following happened.

Uploaded to SS correctly but after that, some files (jpgs) got corrupted in my hard disk and got 0bytes

Rebooted and nothing.

Today the other files (all jpgs the videos are still ok) have 0 metadata. No keywords, no title, categories or anything.

Any idea on what is wrong??

Backup is done, no problem on that.

I don�t think is my hd fault when first some photos have metadata and few minutes later after a reboot they do not have any metadata (attached releases, etc)

I experienced  similar strange behavior yesterday and not resolved yet.
I went on a tree weeks trip and therefore I didn't use StockSubmitter for that time frame.
Turned on my computer last night and started StockSubmitter. The software performed the updates, and when started I noticed that none of the already images had the model release attached. I always have a back up copy of the stocksubmitter  configuration (SSB) and tried to import the previous configuration (three weeks old). I was presented with a window telling me to choose the file I wanted to import. I went through the import process but nothing changed. Model releases were not there. Had no problem with metadata. Of course I do have backup file of everything I have on the hard drive, so no worries there.
To avoid further problems, closed the software turned my computer off, and I am thinking of trying tonight again. I am not sure if reinstalling the software will resolve the issue. Otherwise I might have to rebuild my model releases file in stocksubmitter, and use for new uploads. Will see.
Any advice will be appreciated.

I experienced  similar strange behavior yesterday and not resolved yet.
I went on a tree weeks trip and therefore I didn't use StockSubmitter for that time frame.
Turned on my computer last night and started StockSubmitter. The software performed the updates, and when started I noticed that none of the already images had the model release attached. I always have a back up copy of the stocksubmitter  configuration (SSB) and tried to import the previous configuration (three weeks old). I was presented with a window telling me to choose the file I wanted to import. I went through the import process but nothing changed. Model releases were not there. Had no problem with metadata. Of course I do have backup file of everything I have on the hard drive, so no worries there.
To avoid further problems, closed the software turned my computer off, and I am thinking of trying tonight again. I am not sure if reinstalling the software will resolve the issue. Otherwise I might have to rebuild my model releases file in stocksubmitter, and use for new uploads. Will see.
Any advice will be appreciated.

Make sure there is a correct path to the releases folder specified in settings.
Also make sure there are release images in that folder.
If you've included the releases in the backup they should've been restored together with the configuration though.