www.neuron.yale.edu

I've been using NEURON 7.3 for about a year now, and it worked quite well on my old computer. Unfortunately, that computer died, and on my new computer I can't get NEURON 7.3 to successfully run the same files that worked on my old computer. My new one is a Windows 7 machine, as was my old one. Today I installed NEURON 7.3 on my new machine using the file nrn-7.3.alpha-755.i686-pc-cygwin-setup.exe. When I tried to run one of my old files (which worked on NEURON 7.3 on my old computer), I got the following error:

nrniv: CellParamSet is not a template
in TGbignet2.tem near line 62
synCellSet = new CellParamSet() //reads in the cells.par into synCellSet
^
xopen("TGbignet2.tem" )
execute1("{xopen("TGbignet2.tem")}" )
load_file("./templates/TGbignet2.tem" )
nrniv: syntax error
in TGbignet2.tem near line 64
Npyr = synCellSet.cellSet.object(0).N


I am very confused by this error because it is being generated in the first few lines of my simulation:
The file manycells.tem defines the template CellParamSet, yet somehow when it is used in TGbignet2.tem, it generates an error. I'm not really sure where to go from here in troubleshooting this, since it seems obvious to me that I'm defining CellParamSet before it is used in TGbignet2. Thanks in advance for the help.

First, have you thrown away your old nrnmech.dll (and any .c or .o files that were generated as a byproduct of running mknrndll) and recompiled your mod files? I admit that thisdoesn't look like the kind of message that would result from using a nrnmech.dll that is incompatible with the installed NEURON executable, but on the off chance . . .

Second, perhaps you're running into an obscure bug in NEURON 7.3.alpha-755. You might try uninstalling it and getting the most recent alpha installer http://www.neuron.yale.edu/ftp/neuron/v ... -setup.exe

If that doesn't work, I'd ask you to zip up the necessary hoc and ses files and send them to
ted dot carnevale at yale dot edu
so we can reproduce the error and isolate the cause and cure of this problem.

Actually, your suggestion to delete the old nrnmech.dll file and compile a new one worked--thanks so much!

When switching from one version of NEURON to another, it's necessary to discard any old nrnmech.dll files. Probably also a good idea to delete old .o and .c files (they aren't useful anyway).