All project errors in Eclipse----Project All Red Fork Solutions

Today I met a super depressed thing, Eclipse new project all have Red fork, I initially thought I might be because these two days have been in the configuration of the NDK development environment, is not accidentally put that place to configure, and then create a new project when the project will appear red Fork effect. Then I clean it up, and the big cake, all the projects are wrong.

Open the following error prompt:

Wrong meaning: Debug Certificate is out of date. Baidu a bit, sure enough, there are similar problems, said to be involved in a private key time-limit problem.

The solution is: Enter: C:\Documents and settings\administrator\.android Delete: Debug.keystore and ddms.cfg reopen Eclipse and then clean up It's OK.

Note: Open the problem view of eclipse (if you have closed the problem view under Window->show view), and then in the view you can see the root cause of the project.

Cause Analysis: Android requires that all programs must have a signature, otherwise the program will not be installed. In our development process, ADT uses debug KeyStore, which is set in Preference->android->buid in Eclipse. Debug KeyStore is valid for one year by default, and if you started Android a year ago, it's likely that debug KeyStore expires one year later, causing engineering errors or inability to generate APK files and so on (think I was really a year ago this time started the development of Android apps).