Just follow the steps given below and define the variable path
Step 1: First of all, copy the path of Lotus Notes from its saving location.
Step 2: Go to My Computer or This PC and right-click on it. Here, select the Properties option from the list.
Step 3: In the opening Setting wizard, click on the Advanced system settings.
Step 4: Next System Properties tab pop-up on your screen; go for the Environmental Variable option.
Step 5: Here, you will get two Environmental variables: One is the User variable for this, and another one is the System variable.
Step 6: Just Find the variable path from the system variable box. Suppose you can't find it; click on the New button.
Step 7: Here, enter the variable name as the path and variable value (Copied Lotus Notes Path) and click on the Ok button.
Step 8: Suppose you find the path of the variable in the System Variable box.