Hi Wayne, Unfortunately this molecule has 4 strange chemComp. I tried to copy the folder project1/ccp/molecule to project2/ccp. That didn't work automagically. I guess this leads to a general question. Is there a general way to transfer a molecular system from one project to another? This molecule in question is used in the lab a lot and I made this molecule in one project. Unfortunately I don't remember how I did it (I should check the mailing list because I enlisted a lot of help from you and Wim). The gist is that it is an modified RNA with all U & C bases having a Fluorine in the 2' position and all A and G bases but 2 have O-methyl groups in the 2' position. These chemComp are A2m, CFL, Omg and Umf. I had to download them from the EBI website. Thanks, Justin Unfortunately what the code is doing there is generic enough that it's not > obvious what is going wrong. But it looks like (at a guess) that the > funny chemComp is not being found. But why it is not being found I don't > know. Is its XML file located in the project-specific directory for the > first project and not in a similar location in the second project? That > might cause a problem like this (but I don't know the details of how this > stuff is being copied over by the dataShifter so I could be wrong). If > that's the problem then it's possible that just copying the XML file over > from the first project to the second one before you run the dataShifter > would work. (Or it might need some more finessing, because it might not > just pick this up automagically.) >