As a freelancer say for example you developed a web or mobile application for a client as a one time fixed price paid project. You send them the code, install it on their server, and they begin using it for themselves.
Now, normally I'd give my clients 30 days of free bug fixing, before I start charging them for my development time. This gives them a month to work out the kinks, test everything to their satisfaction, and provide feedback while I fix any issues they find at no additional charge.
How long is normal to provide support on critical bugs on a project you are no longer getting paid for? 1 month? 6 months? For ever? Where do you draw the line?