OrcaFlex has a number of features that take advantage of the Python programming language. We work hard to ensure that OrcaFlex is compatible with a wide range of Python versions. However, a couple of recent Python releases have contained bugs that have broken functionality that OrcaFlex relied upon.

• Python version 2.7.11 is affected by issue 26108. This did not affect automation of OrcaFlex from a Python process. The defect meant that when Python was embedded in an OrcaFlex process, for external functions or post-calculation actions, OrcaFlex would crash when it attempted to load the embedded Python modules. We were able to workaround this particular defect and OrcaFlex 10.0e and later do so.
• Python version 2.7.13 is affected by issue 29082. This issue has no impact on embedding Python in OrcaFlex, but instead breaks the import of the OrcFxAPI module from a Python process. At the moment we have no workaround for this defect.

Because of these problems we recommend that you do not install either of these versions of Python. If you must use a version from the 2.7 family then we would recommend 2.7.12.

Update: Since this post was originally written, version 2.7.14 has been released which addresses both of these problems.

Python 2 is now maintained only to add bug fixes, and mainstream development attention for Python is given to Python 3. The problems that we have encountered with 2.7, as described above, lead us to recommend that an up-to-date Python 3 should be used with OrcaFlex if at all possible.

Python 3.6 has very recently been released and the next minor update to OrcaFlex, version 10.1c, will support this.