Hi, I am a freshman to use Chimera. When I run "add charge" of ligand by the tutorial, and the error below appears. I would like to know the reasons and how could I solve this problem. Thank you very much! Charge model: AMBER ff99SB Assigning partial charges to residue ARA (net charge +0) with am1-bcc method Running ANTECHAMBER command: D:/drivers/Chimera 1.5.3rc/bin/amber11/bin\antechamber -ek qm_theory='AM1', grms_tol=0.02, tight_p_conv=0, scfconv=1.d-10, -i c:\users\dingzh~1\appdata\local\temp\tmpkghulj\ante.in.mol2 -fi mol2 -o c:\users\dingzh~1\appdata\local\temp\tmpkghulj\ante.out.mol2 -fo mol2 -c bcc -nc 0 -j 5 -s 2 (ARA) cygwin warning: (ARA) MS-DOS style path detected: c:\users\dingzh~1\appdata\local\temp\tmpkghulj\ante.in.mol2 (ARA) Preferred POSIX equivalent is: /cygdrive/c/users/dingzh~1/appdata/local/temp/tmpkghulj/ante.in.mol2 (ARA) CYGWIN environment variable option "nodosfilewarning" turns off this warning. (ARA) Consult the user's guide for more details about POSIX paths: (ARA) http://cygwin.com/cygwin-ug-net/using.html#using-pathnames (ARA) /usr/bin/antechamber.exe: error while loading shared libraries: ?: cannot open shared object file: No such file or directory (ARA) Error: cannot run ""D:/drivers/Chimera 1.5.3rc/bin/amber11/bin/bondtype" -j part -i ANTECHAMBER_BOND_TYPE.AC0 -o ANTECHAMBER_BOND_TYPE.AC -f ac" in judgebondtype() of antechamber.c properly, exit (ARA) Running: "D:/drivers/Chimera 1.5.3rc/bin/amber11/bin/bondtype" -j part -i ANTECHAMBER_BOND_TYPE.AC0 -o ANTECHAMBER_BOND_TYPE.AC -f ac Failure running ANTECHAMBER for residue ARA Check reply log for details -- Zhaoyang Ding East China University of science and technology Shanghai China