Hi, When I try to open a chimera session file, Chimera asks me to identify the file type, and then stops with the error message below. Can you please advice? I am using MacOSX 10.11.3. Best regards, Luca *** You are now running Chimera version 1.11 (build 41141). Your previous version was 1.10.1 (build 40415). Check the release notes for new features and other info. (To access the release notes, use the Help menu to bring up the User's Guide. Then click the 'Documentation index' link and you will then see a link for the release notes.) Registration file "/Users/lp212/.chimera/registration" has expired. Error while sourcing SsoCdc45.py, line 0: "import cPickle, base64" Unrecognized command: "import" Error while sourcing SsoCdc45.py, line 0: "import cPickle, base64" Unrecognized command: "import" Error while sourcing SsoCdc45.py, line 0: "import cPickle, base64" Unrecognized command: "import" Model 0 (Cdc45_depo.pdb) appears to be a protein without secondary structure assignments. Automatically computing assignments using 'ksdssp' and parameter values: energy cutoff -0.5 minimum helix length 4 minimum strand length 3 Use command 'help ksdssp' for more information. Luca Pellegrini, PhD Department of Biochemistry University of Cambridge 80 Tennis Court Road Cambridge CB2 1GA UK Email: lp212@cam.ac.uk Phone: 0044-1223-760469