diff --git a/doc/forum/How_can_I_determine_why_a_given_file_is___34__used__34____63__/comment_1_30217e593a04cefa30619025d0a58108._comment b/doc/forum/How_can_I_determine_why_a_given_file_is___34__used__34____63__/comment_1_30217e593a04cefa30619025d0a58108._comment
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+[[!comment format=mdwn
+ username="joey"
+ subject="""comment 1"""
+ date="2021-05-10T19:04:00Z"
+ content="""
+Is it in use in git's index? git-annex addunused adds a link to the working
+tree, and also stages it in the index. You said
+"I rm'ed the symlink", but that would leave it in the index, so still used.
+
+(It's also theoretically possible for git-annex unused to incorrectly
+decide something is unused that is not -- it uses a bloom filter which can
+have false positives -- but this is highly unlikely unless your repo has
+a huge number of files in it. The annex.bloomaccuracy and annex.bloomaccuracy
+configs can be used to tweak the bloom filter.)
+"""]]