Due to an issue with the detection of the number of cores for computers that have 16 cores with hyperthreading (or more), Plaxis will raise a bug report stating an “Integer overflow”, after which the program cannot be used.
A workaround is available to solve this that will limit the numbers of cores detected. For this purpose, a special toggle files should be created, called PRETEND_8_CPUS How to create this toggle file: In the Plaxis installation folder, create a subfolder called Toggles. In this folder place a file named after the toggle, all letters in uppercase, and most important, do not add a file extension (it will be an extensionless file). So this file will be called: PRETEND_8_CPUS
Below you can find the Toggle file. It should be placed in the Toggles subfolder of the PLAXIS installation folder. To store this, please right-click the link and choose "Save as". Then make sure to save the file without an extension in the correct folder.
In most cases, when using more than 8 cores per calculation phase, the added boost is not that much: it may even be slower in certain cases due to managing splitting the calculation for multiple cores, and then merging the results.
Since PLAXIS 3D2012.02, this issue has been solved, and PLAXIS 3D Input can be used to its full extend on computers with 16 cores or more. However, for running the calculation using the Pardiso solver, please see the related issue.