Launch the STK License Manager found under Start>Programs>STK Support Tools>License Manager. Once opened, look for the Host ID field at the bottom of the window.
Use the Host ID specified in the field at the bottom of the license manager.
If STK is not yet installed
For XP Users: Click Start>Run to display the "Run" GUI. Type "cmd" in the Run GUI drop-down box next to the word "Open:" and then click the "OK" button to display the command prompt window.
For Vista and 7 Users: Type "cmd" in the text box above the window start button and in a few seconds you should see a pointer to the cmd.exe program. Click on the program shortcut and that will bring up the command prompt window.
Type "ipconfig /all" in the command prompt window and press the "enter" button on the keyboard.
You will see some information in the command prompt regarding your computer's physical address (Host ID a.k.a MAC address).
Look for the section that says "Ethernet Adapter Local Area Connection" and find the Physical Address which should look something like this "XX-XX-XX-XX-XX-XX". Please note that sometimes Host ID that STK might be reading could be the "Ethernet Adapter Wireless Network Connection" or another physical connection on the workstation. Keep in mind that when you enter the Host ID / MAC address will look similar to this "XXXXXXXXXXXX" on the license file.
If for some reason you are not able to see the Physical Address tied to either the "Ethernet Adapter Local Area Connection" or "Ethernet Adapter Wireless Connection," then your security department has probably deactivated the NIC card on the workstation for security reasons. This is common with defense companies who have strict guidelines on how they configure their own workstation. This is a common procedure but one that can be easily corrected. You will need to check with your IT or security department to determine if the NIC card can be activated for work purposes, since all FLEXLM node-locked licenses are tied to the NIC card being operational with the ability to see the Physical Address of either the "Ethernet Adapter Local Area Connection" or "Ethernet Adapter Wireless Connection". Check with them and they should be able to tell you if it is permissible to activate the NIC.