I change = TEXT("<unknown>"); into = (TCHAR*) malloc( MAX_PATH * sizeof(TCHAR) ); it looks like working well now. but sequenced question is, how free this memory I allocate in C?

You should not be using malloc(). Did you miss my mention of Newx(), Newxc() Newxz() and the associated link?

how free this memory I allocate in C?

If you followed the link, you would have seen Safefree()

In my case, I just want to check process name.

I tend to use tasklist for that:

perl -E"my @tasks = map[ (split)[0,1] ], `tasklist /nh`; say qq[@$_] f
+or @tasks"
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