# Known issues¶

## Cannot find msvcr90d.dll¶

If you see this message coming up, find the file PythonDir\Lib\site-packages\numpy\distutils\mingw32ccompiler.py and modify the line msvcr_dbg_success = build_msvcr_library(debug=True) to read msvcr_dbg_success = False (you can comment out the existing line and add the new line immediately after).

## Problems with numerical integration¶

If the beginning of a run takes a long time, the reason might be the automatic determination of a suitable numerical integration algorithm. This can in particular happen for complicated equations where sympy’s solvers take a long time trying to solve the equations symbolically (typically failing in the end). We try to improve this situation (see #351) but until then, chose a numerical integration algorithm explicitly (Numerical integration).

## Cannot find vcvarsall.bat on standard search path¶

If you have Windows and Microsoft Visual Studio 2015 installed, and you are trying to run with OpenMP support, you will see this error. There is a bug in OpenMP support for this version of Visual Studio. You can either install a different version or switch OpenMP off.