We Shortened Every Path in Our Unreal Build. That Wasn’t the Real Fix.
This is a submission for DEV's Summer Bug Smash: Smash Stories , powered by Sentry . We had already done the obvious thing. The Unreal Engine 5 project was copied to a very short build root. Folder names were trimmed. The packaging workspace was deliberately shallow. Cook still failed with the familiar pair: Couldn't save package, filename is too long (... >= 260) AutomationTool exiting with…
This text describes an issue with building an Unreal Engine 5 project using a short build root path. The project failed with an error stating that the filename was too long. The developers shortened the path even further, but this did not resolve the issue. The root cause turned out to be that Windows does not enable long path support by default.
The developers had to set a system registry value to enable long paths and restart the affected processes. This fix allowed the packaging flow to succeed with longer asset paths. The developers learned that while short paths are useful for build hygiene, they are not a substitute for configuring the operating system to support long paths.
They kept using short paths as a safeguard, but verified a successful build by checking that the final artifact existed.
Written by urgent.news from Dev.to's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
