我到处寻找，无法找到解决这个问题的方法。我已经尝试重命名.h / .m文件删除它们并再次创建它们，以及查看问题是否是项目管理器中不在编译源中的文件。
这是错误：
Ld /Users/mabdelhamid/Library/Developer/Xcode/DerivedData/Markschemes-dksalheponzwnocllyohgwmotxho/Build/Products/Debug-iphoneos/Markschemes.app/Markschemes normal armv7
cd "/Users/mabdelhamid/Desktop/Application Backup/MarkSchemes 14:08"
setenv IPHONEOS_DEPLOYMENT_TARGET 6.1
setenv PATH "/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin:/Applications/Xcode.app/Contents/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin"
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang -arch armv7 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk -L/Users/mabdelhamid/Library/Developer/Xcode/DerivedData/Markschemes-dksalheponzwnocllyohgwmotxho/Build/Products/Debug-iphoneos -F/Users/mabdelhamid/Library/Developer/Xcode/DerivedData/Markschemes-dksalheponzwnocllyohgwmotxho/Build/Products/Debug-iphoneos -filelist /Users/mabdelhamid/Library/Developer/Xcode/DerivedData/Markschemes-dksalheponzwnocllyohgwmotxho/Build/Intermediates/Markschemes.build/Debug-iphoneos/Markschemes.build/Objects-normal/armv7/Markschemes.LinkFileList -dead_strip -fobjc-arc -fobjc-link-runtime -miphoneos-version-min=6.1 -framework MessageUI -framework QuartzCore -framework UIKit -framework Foundation -framework CoreGraphics -o /Users/mabdelhamid/Library/Developer/Xcode/DerivedData/Markschemes-dksalheponzwnocllyohgwmotxho/Build/Products/Debug-iphoneos/Markschemes.app/Markschemes
duplicate symbol _penaltyCriteria in:
/Users/mabdelhamid/Library/Developer/Xcode/DerivedData/Markschemes-dksalheponzwnocllyohgwmotxho/Build/Intermediates/Markschemes.build/Debug-iphoneos/Markschemes.build/Objects-normal/armv7/MHTFrontViewController.o
/Users/mabdelhamid/Library/Developer/Xcode/DerivedData/Markschemes-dksalheponzwnocllyohgwmotxho/Build/Intermediates/Markschemes.build/Debug-iphoneos/Markschemes.build/Objects-normal/armv7/MedIFrontViewController.o
ld: 1 duplicate symbol for architecture armv7
clang: error: linker command failed with exit code 1 (use -v to see invocation)
有人帮我解决这个问题。
如果我选择.m文件并从实用程序区域的文件检查器取消选中目标成员资格，则错误消失，但我的课程无法使用。