Operating system: Windows 7 Pro SP1 64 bit
Slicer version: 4.8
Expected behavior: Running normally
Actual behavior: Slicer 4.8 was running successfully on a PC with 8Gb RAM and has stopped - the slicer screen appears but then nothing further happens. Have tried version 4.9 but still have the same problem. Would adding another 8Gb RAM be a good idea?
That sounds like it could be something wrong with your settings - you could try deleting the settings file to see if that fixes things:
(Of course, more RAM can be helpful if you work with big files)
If Slicer does not start after cleaning out settings then follow further instructions described here: https://www.slicer.org/wiki/Documentation/Nightly/Developers/Tutorials/Troubleshooting#Instruction_for_Windows