Hello.
Check DBDriver parameter in netxmsd.conf, it should points to database driver's .so file (should be "DBDriver=/usr/local/netxms/lib/libnxddr_mysql.so" in your case, I assume)
Check DBDriver parameter in netxmsd.conf, it should points to database driver's .so file (should be "DBDriver=/usr/local/netxms/lib/libnxddr_mysql.so" in your case, I assume)