我最近使用Force.com IDE 时，经常提示密码错误。从Google 中终于发现一个解决方法，分享给大家，以供大家参考。
在Force.com IDE 29.0中，IDE 存储我们开发Org 的密码不是在我们的WorkPlace,而是通过强加密的方式存储在特地的地方.（以前的版本不清楚）
I recently installed the latest version of Eclipse (eclipse-java-kepler-R, 220.127.116.1130919-0803) with the Force.com IDE plugin (18.104.22.168310181333). Everything was working fine until this morning, when it had lost the credentials for the project I was working on.
I could re-enter the password and security token, the plugin connected to Salesforce, but as soon as I closed the Force.com IDE settings on the project and re-opened it, the credentials were gone.
Logging into Salesforce, and going to the Login History of my account, I saw the plugin connecting just fine.
How can I get it to start storing the passwords again?
I found a solution. I had to go into the Eclipse preferences and delete the values in "Secure Storage".
1) Select the Window/Preferences item.
2) Go to General/Security/Secure Storage.
3) Select the Contents tab.
4) Select Force Projects and then click the Delete button.
After restarting, Force.com IDE was able to save my passwords again.