If you would like to recover an earlier version of a Sigma estimate (i.e. you forgot to save it or deleted the version by mistake) follow these steps.
1. Open the latest saved version of the estimate.
2. Click on File> Info.
3. Choose the version of the estimate you would like to edit.
NOTICE: Both versions of the estimate are now open (the latest saved version and the version you have recovered).
TIP: Click on Manage Versions (File>Info) to see all of the Sigma backup files in the folder “SigmaRecovery.”