1. A method for identifying unmatched registry entries, comprising: scanning a file system and discovering software; collecting first attributes of the discovered software; collecting native registry entries; comparing the first attributes of the discovered software against second attributes of the collected native registry entries based on a filtering rule, thereby grouping the native registry entries into two groups, wherein one group represents matched registry entries and the other group represents unmatched registry entries, thereby identifying the unmatched registry entries as unequivocal entries for further software discovery; comparing by a similarity comparison a first member of the group of unmatched registry entries with a second member of the group of unmatched registry entries; and assigning a complete group of related registry entries relating to the second member of the group of unmatched registry entry to the group of matched registry entries if a result of the similarity comparison is higher than a predefined related threshold, and if the first member of the group of unmatched registry entries was assigned before into the group of matched registry entries.