I am new to the CCPNMR world and structure calculation using aria. I am trying to get started by using the "Extend-NMR 4: Structure Calculation with ARIA" Tutorial. However, when I use the Demofile CcpnDemo006.tgz and doing the steps in "Running ARIA", I get the following errors when running Aria: ... MESSAGE [CNS]: CNS output files have been copied to /home/nmr/Desktop/ CcpnDemo006/run1/structures/it0/cns MESSAGE [Job manager]: shutdown. Traceback (most recent call last): File "/home/nmr/nmr/aria2.3/aria2.py", line 903, in <module> verbose_level, use_condor=condor) File "/home/nmr/nmr/aria2.3/aria2.py", line 813, in run_aria project.go(use_condor) File "/home/nmr/nmr/aria2.3/src/py/aria/Project.py", line 1574, in go self.run_protocol(first_iteration) File "/home/nmr/nmr/aria2.3/src/py/aria/Project.py", line 1580, in run_protocol last_iteration = self.getProtocol().go(iteration, self.getMolecule()) File "/home/nmr/nmr/aria2.3/src/py/aria/Protocol.py", line 1730, in go iteration = self.start(iteration, molecule) File "/home/nmr/nmr/aria2.3/src/py/aria/Protocol.py", line 1714, in start return self.run_protocol(molecule, iteration) File "/home/nmr/nmr/aria2.3/src/py/aria/Protocol.py", line 2182, in run_protocol is_first_it) File "/home/nmr/nmr/aria2.3/src/py/aria/Protocol.py", line 2137, in run_iteration self.error(StandardError, err_msg) File "/home/nmr/nmr/aria2.3/src/py/aria/ariabase.py", line 211, in error raise exception, msg StandardError: USER ERROR <aria.Protocol.Protocol> File "/home/nmr/nmr/aria2.3/src/py/aria/Protocol.py", line 2182 in run_protocol Structure calculation failed for structure 1. ... When looking into one of the generated refine.out files from CNS, I find the following errors: " -------------------------- Torsion Topology ----------------------------------- Please send a bug report to [log in to unmask] Please increase the "maximum number of distinct bodies" (torsion_maxtree) and re-run. %TORSION:TOPOLOGY error encountered: Fatal Topology Error (CNS is in mode: SET ABORT=NORMal END) ***************************************************** ABORT mode will terminate program execution. ***************************************************** Program will stop immediately." However, I can not find the parameter "torsion_maxtree" in the config file and don't know where I could add it. I get those errors both when running aria locally as well as on the grid. The used software versions are Analysis 2.1.5, Aria 2.3 I started by using CNS 1.3, putting the src files from the Aria directory to CNS sources and compiling CNS. Then I did the same for CNS 1.21 and 1.2. Each gives me the maxtree-error. All updates in ccpnmr analysis are done. Any hints in which direction I should search? Is this a software issue (CNS) or are some of the parameter files incorrect? Is it correct to apply the files from the aria cns/source directory although the install manual states 'cns_solve_1.1'? Best regards, Sebastian Eckert