
A spokesperson for Symantec didn't immediately return a phone call seeking additional information.
The false positives appear to be caused by a faulty update of Symantec's anti virus signatures that was distributed on 1 July. According to user comments, the problem was repaired on 3 July.
The faulty detection caused the anti virus software to remove or quarantine the allegedly infected files. The problems only occurred with version 2.17 of NSIS, not the current version 2.18.
The Nullsoft Scriptable Install System offers a standard way for software developers to have their products installed on a system. It is used by numerous applications including the WinAmp media player, the Kaspersky anti virus software and the game Settlers II.
Last week's error marks that fourth time that Symantec mislabels NSIS as spyware, according to an overview on the project's webpage.
NSIS gets mislabelled as spyware on a regular basis. Microsoft tops the list. It's anti-spyware software has goofed up on five occasions.