I’ve just installed InvoicePlane for the first time and got it running.
If i click on the “Add Client” or “Enter Payment” or “Custom Fields” settings, i get an error from my browser (Chrome): ERR_EMPTY_RESPONSE
And again are you serious? Read the massive red box at the top of this page! This is issue has been mentioned and resolved countless times InvoicePlane 1.5.4 released