Notepad++ log analysis

Delete all lines which doesn’t match a pattern

This pattern looks for everything that’s not [error] and deletes it from the file

^(?!.*\[error\]).*$

ctrl + F and replace everything with empty

See log files with colors

Go to C:\Users\your_user\AppData\Roaming\Notepad++\userDefineLangs. If the folder doesn’t exist, create it.

Create a file logSyntax.xml with the following content

<NotepadPlus>
    <UserLang name="logSyntax" ext="log" udlVersion="2.1">
        <Settings>
            <Global caseIgnored="yes" allowFoldOfComments="no" foldCompact="no" forcePureLC="0" decimalSeparator="0" />
            <Prefix Keywords1="yes" Keywords2="no" Keywords3="yes" Keywords4="yes" Keywords5="yes" Keywords6="no" Keywords7="no" Keywords8="no" />
        </Settings>
        <KeywordLists>
            <Keywords name="Comments">00WARN 01 02 03 04</Keywords>
            <Keywords name="Numbers, prefix1"></Keywords>
            <Keywords name="Numbers, prefix2"></Keywords>
            <Keywords name="Numbers, extras1"></Keywords>
            <Keywords name="Numbers, extras2"></Keywords>
            <Keywords name="Numbers, suffix1"></Keywords>
            <Keywords name="Numbers, suffix2"></Keywords>
            <Keywords name="Numbers, range"></Keywords>
            <Keywords name="Operators1"></Keywords>
            <Keywords name="Operators2"></Keywords>
            <Keywords name="Folders in code1, open"></Keywords>
            <Keywords name="Folders in code1, middle"></Keywords>
            <Keywords name="Folders in code1, close"></Keywords>
            <Keywords name="Folders in code2, open"></Keywords>
            <Keywords name="Folders in code2, middle"></Keywords>
            <Keywords name="Folders in code2, close"></Keywords>
            <Keywords name="Folders in comment, open"></Keywords>
            <Keywords name="Folders in comment, middle"></Keywords>
            <Keywords name="Folders in comment, close"></Keywords>
            <Keywords name="Keywords1"></Keywords>
            <Keywords name="Keywords2"></Keywords>
            <Keywords name="Keywords3"></Keywords>
            <Keywords name="Keywords4"></Keywords>
            <Keywords name="Keywords5"></Keywords>
            <Keywords name="Keywords6"></Keywords>
            <Keywords name="Keywords7"></Keywords>
            <Keywords name="Keywords8"></Keywords>
            <Keywords name="Delimiters">00 01 02 03INFO 04 05202 06DEBUG 07 08202 09ERROR 10 11202 12TRACE 13 14202 15 16 17 18 19 20 21 22 23</Keywords>
        </KeywordLists>
        <Styles>
            <WordsStyle name="DEFAULT" fgColor="FFFFFF" bgColor="FFFFFF" colorStyle="1" fontStyle="0" nesting="0" />
            <WordsStyle name="COMMENTS" fgColor="0080FF" bgColor="FFFFFF" fontStyle="7" nesting="0" />
            <WordsStyle name="LINE COMMENTS" fgColor="FFFF00" bgColor="FFFFFF" colorStyle="1" fontStyle="0" nesting="0" />
            <WordsStyle name="NUMBERS" fgColor="B2C57F" bgColor="FFFFFF" colorStyle="1" fontStyle="3" nesting="0" />
            <WordsStyle name="KEYWORDS1" fgColor="00CA28" bgColor="FFFFFF" colorStyle="1" fontStyle="3" nesting="0" />
            <WordsStyle name="KEYWORDS2" fgColor="0080FF" bgColor="FFFFFF" colorStyle="1" fontStyle="3" nesting="0" />
            <WordsStyle name="KEYWORDS3" fgColor="8000FF" bgColor="FFFFFF" colorStyle="1" fontStyle="3" nesting="0" />
            <WordsStyle name="KEYWORDS4" fgColor="FF0000" bgColor="FFFFFF" fontStyle="3" nesting="0" />
            <WordsStyle name="KEYWORDS5" fgColor="FF0080" bgColor="FFFFFF" colorStyle="1" fontStyle="3" nesting="0" />
            <WordsStyle name="KEYWORDS6" fgColor="000000" bgColor="FFFFFF" fontStyle="0" nesting="0" />
            <WordsStyle name="KEYWORDS7" fgColor="FF0000" bgColor="FFFFFF" colorStyle="1" fontStyle="3" nesting="0" />
            <WordsStyle name="KEYWORDS8" fgColor="000000" bgColor="FFFFFF" fontStyle="0" nesting="0" />
            <WordsStyle name="OPERATORS" fgColor="FF0080" bgColor="FFFFFF" colorStyle="1" fontStyle="1" nesting="0" />
            <WordsStyle name="FOLDER IN CODE1" fgColor="00FF80" bgColor="FFFFFF" fontStyle="7" nesting="0" />
            <WordsStyle name="FOLDER IN CODE2" fgColor="0080FF" bgColor="FFFFFF" fontStyle="7" nesting="0" />
            <WordsStyle name="FOLDER IN COMMENT" fgColor="0080FF" bgColor="FFFFFF" fontStyle="7" nesting="0" />
            <WordsStyle name="DELIMITERS1" fgColor="FF8040" bgColor="FFFFFF" colorStyle="1" fontStyle="3" nesting="0" />
            <WordsStyle name="DELIMITERS2" fgColor="61D502" bgColor="FFFFFF" colorStyle="1" fontStyle="0" nesting="0" />
            <WordsStyle name="DELIMITERS3" fgColor="4FA7FF" bgColor="FFFFFF" colorStyle="1" fontStyle="0" nesting="0" />
            <WordsStyle name="DELIMITERS4" fgColor="FF0000" bgColor="FFFFFF" colorStyle="1" fontStyle="0" nesting="0" />
            <WordsStyle name="DELIMITERS5" fgColor="8080FF" bgColor="FFFFFF" colorStyle="1" fontStyle="0" nesting="0" />
            <WordsStyle name="DELIMITERS6" fgColor="000000" bgColor="FFFFFF" fontStyle="0" nesting="0" />
            <WordsStyle name="DELIMITERS7" fgColor="C0C0C0" bgColor="FFFFFF" colorStyle="1" fontStyle="1" nesting="0" />
            <WordsStyle name="DELIMITERS8" fgColor="000000" bgColor="FFFFFF" fontStyle="0" nesting="0" />
        </Styles>
    </UserLang>
</NotepadPlus>

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