Hi all: I really appreciate Emil Lundberg, Paul Gideon Dann, Temlin Oliv?r, , Guus Snijders' great suggestion, you are right, that's my fault to use /dev/mapper/arch_root_image as the root partition, now I can login the system,it seems my system is working now. There are two things I do today (my mistakes) based on your suggestion: 1. Instead of using /dev/mapper/ arch_root_image, I use /dev/sda3 as my root partition, and mount first. 2. I copy the files /bin/* to /mnt/bin, so that the error message "failed to run command /bin/sh, no such file or directory" will not exists. I don't see this solution in the internet, I am just think it by myself, so maybe this can help other people with the same problem if what I have done is correct. I don't know how to appreciate all of you, the community. I am so glad to fix this problem now. During the process, I have learned a lot of things, and become more familiar with arch linux, and also love it more (I always love the things more when I get more familiar with). The feeling is strange, at beginning, I see that problem, I have no idea, and become very worried about that. I am considering that time I am failers, just hoping some angel can come and solve that problem for me ... But now, I start learning these things, about what's happening, and with your help, I become more and more confident. Thank you all. I hope my experience can benefit other people, especially the new archer, I want to tell you, don't be afraid, go ahead, start learning, asking good question, and then finally you can fix your problems! The last thing I will do is format the window system of my laptop, install arch linux :) Renzhi Cao Cell: 573-825-8874 Email : rcrg4@mail.missouri.edu<https://bluprd0112.outlook.com/owa/redir.aspx?C=HgdIKZwfkkG-ZqHZQdR5l5Qjeol9gdAIEexz2Okb9KSvfYJfxGlJ7wHelHyOveteZCNx50ztf78.&URL=mailto%3arcrg4%40mail.missouri.edu> http://web.missouri.edu/~rcrg4/