Hello everyone I have successfully upgraded 17.11.06 to 18.05. In system preferences i have changed Elastic search engine instead of zebra server for data searching. I got these error. Software error: Can't locate Catmandu/Store/ElasticSearch.pm in @INC (you may need to install the Catmandu::Store::ElasticSearch module) (@INC contains: /usr/share/koha/lib /etc/perl /usr/local/lib/x86_64-linux-gnu/perl/5.24.1 /usr/local/share/perl/5.24.1 /usr/lib/x86_64-linux-gnu/perl5/5.24 /usr/share/perl5 /usr/lib/x86_64-linux-gnu/perl/5.24 /usr/share/perl/5.24 /usr/local/lib/site_perl /usr/lib/x86_64-linux-gnu/perl-base) at /usr/share/koha/lib/Koha/SearchEngine/Elasticsearch/Search.pm line 50. BEGIN failed--compilation aborted at /usr/share/koha/lib/Koha/SearchEngine/Elasticsearch/Search.pm line 50. Software error: [Mon May 28 09:26:47 2018] search.pl: Can't locate Catmandu/Store/ElasticSearch.pm in @INC (you may need to install the Catmandu::Store::ElasticSearch module) (@INC contains: /usr/share/koha/lib /etc/perl /usr/local/lib/x86_64-linux-gnu/perl/5.24.1 /usr/local/share/perl/5.24.1 /usr/lib/x86_64-linux-gnu/perl5/5.24 /usr/share/perl5 /usr/lib/x86_64-linux-gnu/perl/5.24 /usr/share/perl/5.24 /usr/local/lib/site_perl /usr/lib/x86_64-linux-gnu/perl-base) at /usr/share/koha/lib/Koha/SearchEngine/Elasticsearch/Search.pm line 50. [Mon May 28 09:26:47 2018] search.pl: BEGIN failed--compilation aborted at /usr/share/koha/lib/Koha/SearchEngine/Elasticsearch/Search.pm line 50. Compilation failed in require at /usr/share/koha/lib/Koha/SearchEngine/Search.pm line 54. -- *Muhammad Arshad Iqbal* Assistant Librarian at Publishing and Student Affairs Directorate, National University of Science and Technology (NUST) Islamabad. Phone number:051-90851371 Cell no.+923444900809