Recuva finding lots of files then shuts down

I am tying to recover files from a crashed drive. It crashed due to power supply failure. Drive is still good. Its a 1.8 TB Western Digital. Power supply now replaced, motherboard replaced

Two nights ago I had Recuva running for about 26 hours ( the screen said 4 hours to go) at 0500 hrs I saw it still doing first pass 70% done with over a million files found.

I checked slightly later and Recuva had shut itself off and any recovered info lost.

Now this morning I was less than 20% through a scan for photo files and Recuva shut down again losing all info. In each case there is no power interruption and Windows has no shutdown as I have the Norton antirus disabled to become active on restart. Norton did not restart.

Any thoughts on why this should happen would be appreciated.

System previously was Win 7 Home Premium fully updated. Had Recuva fail on that. At that time motherboard was Intel, DH61WW with Intel i3 CPU 8 GB DDR3 DRAM X2 (almost new)

Present set up, new motherboard Gigabyte H61M-DS2, memory as above, processor as above, Win 7 Home edition not updated yet.

Are there any:

* Crashdumps in the Recuva folder?

* Application errors logs listed in Windows Event Viewer that point to Recuva?

If you have any of those it might help figure out the issue.