Hello,
sir i have found the actual error please help me to resolve it. im attaching the screenshot for your reference.
This is a strange error. It looks like some files could not be generated.
I would first try and re-executed the cell with './simfactory/bin/sim build' in it, ie:
./simfactory/bin/sim build -j2 --thornlist ../einsteintoolkit.th
and if that fails, enter into a new cell:
%%bash make sim-realclean
to clean up the failed build, then try the './simfactory/bin/sim build' cell once more.
If you want to, please download the current notebook (incl. the error message) and forward it as an attachment. My answer won't change but it may help understand why you ended up in this situation and possible prevent this from happening again in the future.
Yours, Roland