On startup I get the message "there was a problem starting windows/system32/NvCpl.dll" How can I prevent this from appearing each time.

This is caused by a NVidia Control Panel applet not being loaded correctly. This is not critical, but means you won't have access to it in Control Panel. To disable it, run msconfig.exe, and find the related entry in the startup programs. Uncheck it, and reboot the pc.If you found this post helpful, please give it a "Helpful" vote. If it answered your question, remember to mark it as an "Answer".

I followed your advise. However as well as getting the original message it now also says C:Windows/system32/NvCpl.dll is not a valid Win32 application.

That's strange. In that case undo what you did by running msconfig again, and selecting what you unchecked (or just choose Normal Startup as opposed to Selective Startup), and restart. Suggestion: Uninstall and re-install your NVidia software. If you found this post helpful, please give it a "Helpful" vote. If it answered your question, remember to mark it as an "Answer".

I uninstalled NVidia. I don't know what this is so I did not reinstall it (Do I need it?) All I do is emailing and web surfing basically. OK, now that original message has gone but now in its place I get "there was a problem starting C:/Windows/system32/NvMcTray.dll. I don't see this in the change/uninstall list.