This issue was reported manually by mmirilovic.
It already has 20 duplicates 


Build: NetBeans IDE 7.1.1 (Build 201203012225)
VM: Java HotSpot(TM) 64-Bit Server VM, 20.8-b03-424, Java(TM) SE Runtime Environment, 1.6.0_33-b03-424-11M3720
OS: Mac OS X

User Comments:
GUEST: error

GUEST: i was developing an application ;)

GUEST: open a less-formatted file

GUEST: error

GUEST: opened .less file after installing lesscss plugin

GUEST: Scrolling through a .less file

GUEST: less plugin crashes on encountering this. should not crash and show error on that line instead.

GUEST: add .less file to project resulting in the loss of the navigation box and the file is non editable.

GUEST: open netbeans and the error occured...
only have 2 project open
1 wordpress and 1 yii framework application




Stacktrace: 
org.lesscss.jcclexer.TokenMgrError: Lexical error at line 0, column 0.  Encountered: "_" (95), after : ""
   at org.lesscss.jcclexer.LessCSSParserTokenManager.getNextToken(LessCSSParserTokenManager.java:0)
   at org.lesscss.lexer.LessCSSLexer.nextToken(LessCSSLexer.java:0)
   at org.netbeans.lib.lexer.LexerInputOperation.nextToken(LexerInputOperation.java:193)
   at org.netbeans.lib.lexer.inc.IncTokenList.tokenOrEmbeddingImpl(IncTokenList.java:179)
   at org.netbeans.lib.lexer.inc.IncTokenList.tokenOrEmbedding(IncTokenList.java:174)
   at org.netbeans.api.lexer.TokenSequence.moveNext(TokenSequence.java:457)