Applicable Versions
Applicable to all Versions


Applicable Releases
Applicable to all Release



There could be several reasons for NetSim not opening on shortcut double click. 

One of the reasons could be insufficient memory that is allocated to JAVA in your system. We recommend you to allocate at least 1024 MB or NO such restrictions for JAVA memory allocation in the environment variable settings.


(i.e) Environment Variable JAVA memory to 1024 MB (_JAVA_OPTIONS -Xmx1024M) or you can delete this entry from the list.


  • Go to Start > Search Environment Variable > Click on Edit the System Environment Variable
  • Click on Environment Variables
  • Search for _JAVA_OPTIONS either under System or User Variables
  • Either Delete the entry or change the value to -Xmx1024M