Why "The system cannot find the batch label specified" is thrown even if label exists?

While running a batch file in Windows XP I have found randomly occurring error message:

The system cannot find the batch label specified name_of_label

Of course label existed. What causes this error?

Solution

Actually, you need 2 conditions for this to happen:

the batch file must not use CRLF line endings
the label you jump to must span a block boundary (as opposed to and :end label wich is just a shortcut to the end of your script)

See. The system cannot find the batch label specified (by and Batch-as-batch-can!

David A. Gray mentions in the comments seeing (on Windows 10) what Marshal's answer showed in 2014 (presumably on Windows 7 or 8): a script/batch program (.bat or .cmd) executed without CALL would trigger an eol conversion.

I've written hundreds of batch scripts over the last 35 years, and the only time I've ever had an issue with labels not being found was when the file's line breaks got converted from Windows (CR/LF), which works, to Unix (LF), which doesn't.

Feb. 2020, kinar adds in the comments:

Just encountered this issue on a Win7 machine.
Turns out this error can also be generated when trying to CALL another .bat file if that file doesn't exist on the system.
In my case, I was trying to call the Visual Studio vcvarsall.bat file on a system without VS installed.

See jeb's answer for more: it was a case of an undefined label.

Note: in a Git repository, I would recommend a .gitattributes file with the directive:

*.bat   text eol=crlf

If you change it afterward, you need, with Git 2.16+ (Q1 2018):

cd /path/to/repo
git add --renormalize .
git commit -m "apply new .gitattributes"