C5 errors are typically buffer overruns, sometimes caused by the C++ programmer mistakenly expecting a string to be null-terminated. So if you see a C5 error, and you know what function or command it is occurring in, the first thing to do to work around the issue is to try null-terminating your strings.

In experimenting with the TEXTMERGE(), I find that null-terminating the string prevents the C5 error.

lcMergedString = TEXTMERGE(lcMyString + CHR(0))

I can't guarantee it will solve the problem for you, but it is worth try. MSFT is aware of this particular issue.

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