Hi, Could anyone fix this problem? I use Koha-3.06.02 to install. After installation, everything works well. I would like try use MARC21 and Unimarc in the same system. So I do like this "1.MARC Bibliographic framework 2.New Framework 3.import Unimarc.sql". After created the Unimarc Framework. The system doesn't work well anymore. When I use opac to search,it shows: Software error: Can't call method "data" on an undefined value at /usr/share/koha/lib/C4/Search.pm line 1488. For help, please send mail to the webmaster (webmaster@ubuntu), giving this error message and the time and date of the error. It can't allow to Add MARC Record. Software error: Tag "" is not a valid tag. at /usr/share/koha/lib/C4/Biblio.pm line 2170 For help, please send mail to the webmaster (webmaster@ubuntu), giving this error message and the time and date of the error. How to fix these problem? Do you have any idea to use MARC21 and Unimarc together? Than you. Peter Zhao