User not found by username
Problem
Sometimes it might happen that a user cannot be found by their username.
Solution
The first step should always be a rebuild of the search index: https://confluence.atlassian.com/x/bEUC
If this is not leading to success it might be, that the user has a so called stop word as username. Confluence will ignore those common words (stop words), including 'and', 'the', 'or', and more, even if they are included within double quotes in order to improve the quality of the search results.
Confluence uses the search engine Lucene. At the moment the following words are defined as stop words:
... , "about", "after", "all", "also", "an", "and", "another", "any", "are", "as", "at", "be", "because", "been", "before", "being", "between", "both", "but", "by", "came", "can", "come", "could", "did", "do", "does", "each", "else", "for", "from", "get", "got", "has", "had", "he", "have", "her", "here", "him", "himself", "his", "how","if", "in", "into", "is", "it", "its", "just", "like", "make", "many", "me", "might", "more", "most", "much", "must", "my", "never", "now", "of", "on", "only", "or", "other", "our", "out", "over", "re", "said", "same", "see", "should", "since", "so", "some", "still", "such", "take", "than", "that", "the", "their", "them", "then", "there", "these", "they", "this", "those", "through", "to", "too", "under", "up", "use", "very", "want", "was", "way", "we", "well", "were", "what", "when", "where", "which", "while", "who", "will", "with", "would", "you", "your", ...
(please refer to the Lucene documentation for a full list of stop words)
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