Hi, yes, the link is correct. But still I have the problem. For example, > tund:~/pwscf.2.1.2ls -l PW/pw.x > -rwxr-xr-x 1 sampyo mkw 6618408 Jan 24 23:34 PW/pw.x* > tund:~/pwscf.2.1.2/PW./pw.x > ./pw.x: Command not found. Thanks, Sampyo