Hi, There is an issue open on UCS4 which is somewhat related: https://github.com/cctbx/cctbx_project/issues/60 We currently don't use UCS4, and your system pyqt4 does. You would have to install (and potentially, compile) it for the cctbx python directly. A 3 minute research from my mobile phone suggests that you might be able to download the sources as tar.gz files and then do something along the lines of cctbx.python -m pip install SIP cctbx.python -m pip install pyqt-source.tar.gz but this is untested, and I haven't used pyqt before. -Markus On 8 Dec 2017 12:19, Gianluca SANTONI wrote: Dear all, I'm having some troubles recently in importing pyqt4 in libtbx.python under Debian8. It used to work with a previous build compiled from the sources, but I don't find a reasonable way to make it work from the bootstrap installation. More details: 1) If I do in libtbx.python sys.path.append('/usr/lib/python2.7/dist-packages/') and "from PyQt4 import QtCore", I get an unidentified symbol: PyUnicodeUCS4_AsLatin1String 2) If I try to compile cctbx as I did in the past "python ../libtbx/configure.py cctbx" no make file is produced. Maybe I'm missing something Thanks everybody for your help. Gian -- Gianluca Santoni, PhD ESRF structural biology group 71 avenue des Martyrs 38027 Grenoble cedex (France) _______________________________________________ cctbxbb mailing list [email protected] http://phenix-online.org/mailman/listinfo/cctbxbb -- This e-mail and any attachments may contain confidential, copyright and or privileged material, and are for the use of the intended addressee only. If you are not the intended addressee or an authorised recipient of the addressee please notify us of receipt by returning the e-mail and do not use, copy, retain, distribute or disclose the information in or attached to the e-mail. Any opinions expressed within this e-mail are those of the individual and not necessarily of Diamond Light Source Ltd. Diamond Light Source Ltd. cannot guarantee that this e-mail or any attachments are free from viruses and we cannot accept liability for any damage which you may sustain as a result of software viruses which may be transmitted in or with the message. Diamond Light Source Limited (company no. 4375679). Registered in England and Wales with its registered office at Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, United Kingdom