Error Messages/40564

Error message

SolverSDK: Engine Library could not be found


The DLL for an add-on solver engine is missing, or the registry settings for the add-on engine are incorrect.

This error is triggered when you attempt to use the mal-configured add-on solver engine, for example by specifying the add-on engine name in the «engine» parameter of DefineOptimization or specifying the engine name in the first parameter of OptEngineInfo.


To find the source of this problem, you'll need to first identify the engine name being requested. For purposes of example, let's suppose it is "MOSEK". In your own case, find the offending function -- for example, if it is DefineOptimization, determine what name is being passed to the «engine» parameter.

Next, you'll need to run RegEdit.exe to examine your system registry. When using RegEdit, always take extra care not to change or delete registry settings inadvertently. You'll need to find the "hive" that contains the setting for the engine name. From within RegEdit, examine the following hives in the indicated following order until you find one containing a value matching your engine name:

If you are running Analytica 64-bit, look in:

  • HKCU/Software/Lumina Decision Systems/4.3x64/SolverEngines
  • HKLM/Software/Lumina Decision Systems/4.3/SolverEngines

If you are running Analytica 32-bit in a 64-bit Windows operating system, look in:

  • HKCU/Software/Lumina Decision Systems/4.3/SolverEngines
  • HKLM/Software/Wow6432Node/Lumina Decision Systems/4.3/SolverEngines

If you are running Analytica in a 32-bit Windows operating system, look in:

  • HKCU/Software/Lumina Decision Systems/4.3/SolverEngines
  • HKLM/Software/Lumina Decision Systems/4.3/SolverEngines

In one of these hives, you should find a name-value pair matching the name of your requested solver engine (e.g., "MOSEK"), and having file path as its value. For example, you might see:

MOSEK (REG_SZ) = C:\Program Files\Frontline Systems\Add-on Engines V10\Bin\MosekEng.dll

Pay very close attention to the file path that appears. The problem might be that there is a typo in the registry setting.

Next, check that a file with the exact path recorded in the registry value exists. The error indicates that it does not, so perhaps it has been moved or removed.


If the solver engine DLL is no longer present (e.g., it has been removed or uninstalled), then you should probably just delete the registry entry (e.g., the MOSEK value in our example).

If the file exists somewhere other than the location specified by the registry entry, or if the registry entry has a typo, then correct the registry entry from within regedit. Right-click on the value and select Modify.

If you encounter a case not covered by this description, than please add it to this wiki page.

See Also


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