Rundll32 has performed an illegal operation and will be shut down. 

Also, Rnaapp.exe caused an invalid page fault in module kernel32.dll 

or, Rnaapp caused an invalid page fault in module rnaapp.exe. 

These error messages can occur if you are running the retail version of Windows 95, and you install Dial-Up Networking using a Microsoft Windows 95 OEM Service Release 2 (OSR2) CD-ROM.  Uninstall Dial Up Adapter and re-install it using the correct CD.

Refer to Microsoft article #Q182293 for more information.