Probably because it's not a standard notation. The standard notation is P21212.
I would reindex and run again. Klaus PhilEvans wrote:
Is there a reason why Arp/warp doesn't like space group P 21 2 21? Phil
-- Dr. Klaus Piontek Albert-Ludwigs-University FreiburgInstitute of Organic Chemistry and Biochemistry, Room 401 H Albertstrasse 21 D-79104 Freiburg Germany
Phone: ++49-761-203-6036 Fax: ++49-761-203-8714 Email: [EMAIL PROTECTED] Web: http://www.chemie.uni-freiburg.de/orgbio/w3platt/