Source Build Problem: Failed to download due to filename

I have built previous versions of UE4 successfully but, when I tried to build the 4.11 I had problems when running the Setup.bat

Failed to download ‘’: The specified path, file name, or both are too long. The fully qualified file name must be less than 260 characters, and the directory name must be less than 248 characters. (PathTooLongException)

I ALSO had this problem when trying to build UE4 with hairworks previously. Any suggestions?

Hi Xaith_EoL,

Simplify the path. For example if your source is in C:\Users<username>\Documents\Subfolder\subfolder\UnrealEngine then put it in something shorter, like C:\UE4Source\ for example.
That will solve your problem.


In Windows API the maximum file path length is 260 characters. Do what Algorithman said.

I figured it out soon after, actually, I thought I didn’t hit post on this… Oh well, maybe it will be helpful to someone.

As stated above I just changed the file location so it works.

Use Long Path tool and fix problem in best possible way.

I used Algorithmans’s solution by taking a whole folder that used a batch file to update others in it to the root directory.

This is the only solution which works