MSVC build errors > LNK1120

LNK1120: unresolved externals

fatal error LNK1120: 1 unresolved externals

LNK1120 is a summary: it ends the link and counts the symbols the linker could not resolve. The errors to fix are the LNK2019 and LNK2001 errors listed before it.

Causes and fixes

1. LNK2019 errors precede it. Each one names a function used but never defined. See how to fix LNK2019.
2. LNK2001 errors precede it. Each one names a static member, a virtual function, or a variable never defined. See how to fix LNK2001.
3. The Error List shows only LNK1120. Open the Build output: it lists every unresolved symbol, with the object file that uses it.

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Related errors: LNK2019, LNK2001. See all guides.