This document discusses various migration paths and tasks involved in migrating applications from an S-series NonStop system running TNS/R to an Integrity NonStop system running TNS/E. It covers migrating applications written in TNS, pTAL, C/C++, and COBOL and discusses changes needed to code, compilers, libraries and other elements to ensure successful migration. Key tasks discussed include recompilation, adjusting for changes in data alignment, compiler directives and functions, and replacing obsolete features.