报错信息如下：
Installing Software has encoutered a problem.An error occurred while collecting items to be installed
Detail:An error occurred while collecting items to be installed
session context was:(profile=PlatformProfile, phase=org.eclipse.equinox.internal.p2.engine.phases.Collect, operand=, action=).
Problems downloading artifact: osgi.bundle,com.python.pydev,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile6986353386050394873.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile6986353386050394873.jar
Problems downloading artifact: osgi.bundle,com.python.pydev.analysis,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile2765980800322631958.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile2765980800322631958.jar
Problems downloading artifact: osgi.bundle,com.python.pydev.codecompletion,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile5817769896724638975.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile5817769896724638975.jar
Problems downloading artifact: osgi.bundle,com.python.pydev.debug,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile2571636681084061843.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile2571636681084061843.jar
Problems downloading artifact: osgi.bundle,com.python.pydev.fastparser,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile5251652448657673995.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile5251652448657673995.jar
Problems downloading artifact: osgi.bundle,com.python.pydev.refactoring,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile5914237358869273637.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile5914237358869273637.jar
Problems downloading artifact: osgi.bundle,org.python.pydev,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile7679411933555608724.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile7679411933555608724.jar
Problems downloading artifact: osgi.bundle,org.python.pydev.ast,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile292084009645105242.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile292084009645105242.jar
Problems downloading artifact: osgi.bundle,org.python.pydev.core,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile7947496018075442225.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile7947496018075442225.jar
Problems downloading artifact: osgi.bundle,org.python.pydev.customizations,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile8239965625154365584.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile8239965625154365584.jar
Problems downloading artifact: osgi.bundle,org.python.pydev.debug,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile356966690632411467.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile356966690632411467.jar
Problems downloading artifact: osgi.bundle,org.python.pydev.django,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile3835497042652402003.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile3835497042652402003.jar
Problems downloading artifact: org.eclipse.update.feature,org.python.pydev.feature,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile4557973523583232662.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile4557973523583232662.jar
Problems downloading artifact: osgi.bundle,org.python.pydev.help,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile662593688633138590.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile662593688633138590.jar
Problems downloading artifact: osgi.bundle,org.python.pydev.jython,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile11266489197245690.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile11266489197245690.jar
Problems downloading artifact: osgi.bundle,org.python.pydev.parser,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile6351892554696202432.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile6351892554696202432.jar
Problems downloading artifact: osgi.bundle,org.python.pydev.refactoring,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile8283962554167943448.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile8283962554167943448.jar
Problems downloading artifact: osgi.bundle,org.python.pydev.shared_core,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile5934382801679672942.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile5934382801679672942.jar
Problems downloading artifact: osgi.bundle,org.python.pydev.shared_interactive_console,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile7792229518047009043.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile7792229518047009043.jar
Problems downloading artifact: osgi.bundle,org.python.pydev.shared_ui,3.8.0.201409251235.
Error reading signed content:/tmp/signatureFile8934376872648029361.jar
An error occurred while processing the signatures for the file: /tmp/signatureFile8934376872648029361.jar
2014年10月31日 17:29:37
问题已解决，自问自答：
在Eclipse下Help--Install New Software下有一个“show only the latest versions of avaiable software”把前的那个勾去掉，这时你就可以选择PyDev的旧版本了，我选择的是2.5的版本，因为最新的版本貌似有些问题，总是安装不成功。
希望能帮助大家。