Spaces and Parenthesis in windows PATH variable screws up batch files

Note for Windows users on 64-bit systems

Progra~1 = 'Program Files' Progra~2 = 'Program Files(x86)'

https://confluence.atlassian.com/display/DOC/Setting+the+JAVA_HOME+Variable+in+Windows

This can happen if there are unescaped parentheses in a line inside a "block" (which also uses parentheses for delimiting).

You can usually fix it by turning on delayed expansion and use variables with !var! instead of %var%. There isn't much more advice I could give without seeing the code.

There should either (a) not be any quotes in the MS-Windows PATH environmental variable (PATH command) or (b) there should be quotes surrounding the entire expression following the (SET command). Unfortunately, this is not very well documented by MS, although they do state that if quotes are used, they will be included in the value of the variable (Windows XP Command Line Reference).

$ SET BLAH="blah blah(1)"
$ ECHO %BLAH%
"blah blah(1)"
$ SET BLAH=blah blah(1)
$ ECHO %BLAH%
blah blah(1)

This can cause problems that are inconsistent and therefore difficult to diagnose. For example if your path includes "C:\Python27", your machine will say "'python' is not recognized as an internal or external command, operable program or batch file." when you try to execute python. However some libraries may still be available.

You do not need to "escape" spaces or parentheses. If you need to escape special characters, then put quotes around the entire expression, including the variable name.

SET "PATH=%PATH%;C:\Program Files (x86)\path with special characters"

or you can use parentheses too.

(SET VAR=can't contain ampersand, parentheses, pipe, gt or lt)

Note, double quotes must come in pairs.

(SET VAR=illegal characters!@#$%^*_-+={}[]\:;""',./?)
echo %VAR%
illegal characters!@#$%*_-+={}[]\:;""',./?

However, there probably are not any characters that are valid pathnames, that would cause a problem with the SET command.