Warning 'Packer returned 1, "..." might still be unpacked'

[th_mi]

I'm using NSIS 3.01 on a Windows 10 System. I get the warning:

1 warning:
Packer returned 1, "C:\Users\TM\AppData\Local\Temp\exehead.tmp" might still be unpacked

The NSIS script never made Problems with NSIS 2.46, and I do not know what this message will exactly tells me. The installer itself is created and seems to work correctly.

Other Setup scritps does not return with this warning.

Any idea for this warning?