Sometimes while running Gorilla Expense logs do not get generated. You will get the following error -

When Gorilla Expense is installed in C:\Program Files (x86) then in order to write to the log file, the following has to happen1) The user needs to be a local administrator and should be given full access to the C:\Program Files (x86)\Gorilla Expense folder2) While running the Gorilla Expense Integration app, press shift and right click the application shortcut and then click "Run as Administrator"
The above two things will ensure the logs get generated.