Fitting Internal Error caused by SignalTap nodes

[Altera_Forum]

Hi, whenever I try to tap any prefit or postfit i2c SDA/SCL lines I get the following error: 

internal error: sub-system: fcuda, file: /quartus/fitter/fcuda/fcuda_register_packer_op_interface.cpp, line: 336  cuda io pad should only drive ibufs  stack trace:   end-trace   quartus ii version 7.2 build 151 09/26/2007 sj web edition The fitter then fails. I really need to check these lines as I can not get the i2c signals to a daughterboard to work. Has anyone else come across this error?

[Altera_Forum]

Try turning off incremental compilation. You won't get the incremental compilation compile time benefit for recompiles after changing SignalTap settings, but turning off incremental compilation might at least get around the internal error. 

 With a later version of Quartus you will probably at least get a normal error message instead of an internal error. I don't expect a newer version to prevent the error entirely, but it might if your situation is different from the one I know about. In any case, a newer version of Quartus might have other benefits for you. You can install a second copy of Quartus (a second copy of the QII 7.2 base version onto which you can add a 7.2 service pack or a regular QII 8.0 install) so that you don't lose access to your QII 7.2 with no service pack.