NMAKE errors and warnings (Uxxxx)

Article
08/03/2021

This section is a reference to the errors and warnings generated by the NMAKE build tool. NMAKE errors and warnings have the form Uxxxx, where xxxx is a four-digit number.

Important

The Visual Studio compilers and build tools can report many kinds of errors and warnings. After an error or warning is found, the build tools may make assumptions about code intent and attempt to continue, so that more issues can be reported at the same time. If the tools make the wrong assumption, later errors or warnings may not apply to your project. When you correct issues in your project, always start with the first error or warning that's reported, and rebuild often. One fix may make many subsequent errors go away.

To get help on a particular diagnostic message in Visual Studio, select it in the Output window and press the F1 key. Visual Studio opens the documentation page for that error, if one exists. You can also use the search tool at the top of the page to find articles about specific errors or warnings. Or, browse the list of errors and warnings by tool and type in the table of contents on this page.

Note

Not every Visual Studio error or warning is documented. In many cases, the diagnostic message provides all of the information that's available. If you landed on this page when you used F1 and you think the error or warning message needs additional explanation, let us know. You can use the feedback buttons on this page to raise a documentation issue on GitHub. If you think the error or warning is wrong, or you've found another problem with the toolset, report a product issue on the Developer Community site. You can also send feedback and enter bugs within the IDE. In Visual Studio, go to the menu bar and choose Help > Send Feedback > Report a Problem, or submit a suggestion by using Help > Send Feedback > Send a Suggestion. Some compiler error topics were created that are not emitted by the compiler and now redirect to this page instead.

You may find additional assistance for errors and warnings in Microsoft Learn Q&A forums. Or, search for the error or warning number on the Visual Studio C++ Developer Community site. You can also search Stack Overflow to find solutions.

For links to additional help and community resources, see Visual C++ Help and Community.

NMAKE fatal errors

NMAKE warnings

NMAKE warning U4001
NMAKE warning U4004
NMAKE warning U4006
NMAKE warning U4007
NMAKE warning U4010
NMAKE warning U4011

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NMAKE errors and warnings (Uxxxx)

NMAKE fatal errors

NMAKE warnings

See also

Feedback

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