So I was trying to trace this problem, and had been doing some work in the Terminal. At some time I tried typing, 'open .', which normally gives a new 'finder' in OS-X. This gave the **same error** (at least partly)... This got me thinking that something might be amiss in .cshrc. So I started to comment out various lines therein, and found that some of my environmental statements regarding nmrpipe were causing the problem: if (-e /usr/local/NMRPipe/com/nmrInit.mac.com) then source /usr/local/NMRPipe/com/nmrInit.mac.com endif if (-e /usr/local/NMRPipe/dynamo/com/dynInit.com) then source /usr/local/NMRPipe/dynamo/com/dynInit.com endif Commenting these out stopped the problem. I can only think that some recent Mac OS upgrade has caused a conflict with the nmrPipe stuff. I'll check in with that. Anyone else using Mac OS-X 10.4.9 and nmrPipe? Thanks! David