Bevin,
I'm not sure there is an easily accessible switch to turn that feature off, although it may be buried in an .xml file somewhere. Whenever you save a proect, the original project that was opened is renamed with a .~stc extension in order to protect your previous work if the newly saved project is corrupted in some way. It doesn't add significantly to the 'save' time and seems like a nice feature that you might not want to disable. - Terry
Thanks Terry,
Yes I know the purpose of the .~stc as a backup and its potential advantages. But since SC does not have a CTRL-Z function to reverse the last step, I save often and as well, I save as a version number at key stages before moving. I am not a fluent user of SC so I often find myself going the wrong direction and so it is handy to return to a known good condition.
Consequently I end up with a lot of ~.stc files that really are unnecessary for me and which are just annoying when looking for files.
Yes I have searched for text strings in the .xml files under \Supplements, strings that could form an XML instruction when autosaving, but without success. So I guess that there is no way to turn off the auto backup. I think there was in earlier versions, but I could be confused with other programs.