Cannot install older versions of Unity - Error 'File Not Found (404)' while downloading Unity

Unity Engine
1

I went to the Unity download archive and downloaded the 5.1.3 installer which is fine, but when running the installer I get a 404 error:

I get the same error with 5.1.4, but I just want 5.1.3.

Edit: To clarify I’m trying to download for Windows 64bit.

2

Try clicking the “Unity Editor 64-bit” option from the list of downloads that appears. This option should download the complete installer. The error you mention makes me think that the installer is downloading pieces from the server.