Surfer v12 and higher can save an SRF file back to Surfer v11 by clicking File | Save As and choosing the appropriate Save as type document format. It cannot save to versions prior to version 11.

Surfer v11 and older cannot save back to older file formats, so, for example, the only product that can save a file in the Surfer 8 SRF format, is Surfer 8. 

If you are trying to save an SRF file to an SRF format older than Surfer 11 so you can send the file to another user who has that older version, some other options are:

1. The user can use the current version to view your file:
   • The other user can download and install the fully-functional, free 14-day trial. They could then open, view, edit, and save the SRF files.
   • The other user can upgrade to the current version of Surfer by December 2020 in order to open SRF files from Surfer v7 and higher. After December 2020, the upgrade program will end, replaced by software maintenance, which includes benefits such as free priority support and free updates to the newest version. One free year of software maintenance is included with the upgrade, so all users with active maintenance can easily share files, as they will all be using the same version.
2. You can export or copy/paste to get another file format to send the user:
   • You can export the Surfer SRF file from your current version to a vector or raster file, and the other users could create a base map from the file in their older version of Surfer. The vector formats (DXF, GSI, MIF, SHP, etc.) may not look exactly the same though, and the raster formats (JPG, TIF, BMP, etc.) are simply images that cannot be edited.
   • You can copy and paste the maps into a Word document and send that to the other user.

Updated November 2021