Feng, Paul, Dave,Bruce, Thanks for the reports. I can reproduce this problem, and I'm pretty sure it's not exactly a problem with the cgi script, but more of an APS/ANL firewall issue. That is, inside the APS firewall, I can run webatoms on this file (unmodified) and get the correct result. It's not simply an issue with 'refer2', because even outside the firewall, I can get other files with a 'refer2' tag in them (try ZnOH2.inp, for example). In addition, leaving the 'refer2' in, and taking the 'refer1' line out also generates a correct output. Also: even outside the firewall, I can get http://cars9.uchicago.edu/atomsdb/YBa2Cu3O7.inp In addition, generating the feff.inp file, and copying this file to http://cars9.uchicago.edu/atomsdb/ybco_feff1.inp I can access that file as well (which might help Feng) So, it appears that the firewall is not simply blocking files that contain the string: refer2: Cava, et al, Physica C 165, p.419, (1990) but does appear to be blocking URLs that contain certain strings (or perhaps strings of a certain length??). I would guess that changing the cgi script to use POST instead of GET would be the simplest way to solve this problem. --Matt