>> Did you install a copy of libxml2 somewhere? look in /usr/local/lib >> -sv [root@sit lib]# ls -alt /usr/local/lib totale 0 drwxr-xr-x 15 root root 352 11 mag 09:18 .. drwxr-xr-x 2 root root 48 11 feb 18:16 . I installed this: [root@sit lib]# rpm -qa | grep libxml2 libxml2-devel-2.6.23-1.2 libxml2-2.6.23-1.2 libxml2-python-2.6.23-1.2 I try this: [root@sit lib]# python Python 2.4.2 (#1, Feb 12 2006, 03:59:46) [GCC 4.1.0 20060210 (Red Hat 4.1.0-0.24)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import yum Traceback (most recent call last): File "<stdin>", line 1, in ? File "/usr/lib/python2.4/site-packages/yum/__init__.py", line 36, in ? import config File "/usr/lib/python2.4/site-packages/yum/config.py", line 29, in ? from repos import Repository File "/usr/lib/python2.4/site-packages/yum/repos.py", line 29, in ? from repomd import repoMDObject File "/usr/lib/python2.4/site-packages/repomd/repoMDObject.py", line 18, in ? import libxml2 File "/usr/lib/python2.4/site-packages/libxml2.py", line 1, in ? import libxml2mod ImportError: /usr/lib/python2.4/site-packages/libxml2mod.so: undefined symbol: xmlSchemaIsValid thank you