SysError in <TFile::Flush>: error flushing file

Merging several several root files using “HAdd” command failed with error message
"SysError in TFile::Flush: error flushing file Target.root (No such file or directory)"

I have used with the current setup of root, I am not sure why it is throwing this error.
I had the idea it might be space issue, but I created lots of space by deleting several of the directories.
But no use.

I am afraid, I do not know what to do now.

Kindly advice,

You could have given the full error message (I think there should have been multiple lines), but my first guess is you are trying to create a file in a directory which doesn’t exist or that you ran out of quota on that volume (e.g. not enough quota to create a file).

Checkout if you can create a output file on the shell command line with