I created a Smath Studio file yesterday
with losts of calculations in it. But today
I could not open the file again. A message box
appeared saying "Index was outside the bounds of the array"

I re-did the work and saved it.

A few hours later, I could not open it again. Same problem
had occurred.

Hope you can fix this soon - regards
(PS: I am using the latest version - 0.97)

Try to open the file with automatic recalculation disabled. Maybe you can locate the problem then.

If the brotjob suggestion fails, could you post the broken file?

Ah ha ..today it is working again.
But I should have added that I was working at two different computers
sharing the same DropBox account. The file was put in the Dropbox,
and it was synchronised to my Home computer. I couldn't open the file
at the Home computer, but I could open it at the Work computer where I originally
created the file. A bit weird though/. Can you please tell me how to post the file to the forum ?. Thank you all.

Just click on the rightmost button on the top of your message or check the attach button when you post a new one.

If the file is too big you can zip it or you can add a dropbox link