Error Message: Error J0051: Undefined Package 'Java.Lang'

• Microsoft Internet Explorer versions 4.0, 4.01, 5 for Windows 95
• Microsoft Internet Explorer versions 4.0, 4.01, 5 for Windows NT 4.0

SYMPTOMS

When you try to compile a Java class using JVC (Microsoft's Java compiler), you may receive the following error message:

error J0051: Undefined package 'java.lang'

CAUSE

This behavior is caused by the Classes.zip file not being present after you install Internet Explorer.

RESOLUTION

WARNING: Using Registry Editor incorrectly can cause serious problems that may require you to reinstall Windows. Microsoft cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk.

NOTE: For information about how to edit the registry, see the online Help in Registry Editor.

To resolve this issue, follow these steps:

1. Click Start, and then click Run.



2. Type clspack -auto in the Open box, and then click OK.
   
   NOTE: This process can take up to two minutes, and during this time no progress indicator is visible.



3. Try to compile a Java class using JVC. If you are still unable to compile, continue to the next step.



4. Use Registry Editor to verify that the key listed below is present. If the key is present, verify that it has the value listed below. If needed, edit the value to match the value listed below. If the key is not present, create it with the value shown here.

   HKEY_LOCAL_MACHINE\Software\Microsoft\Java VM\Classpath
   
   <windir>\java\classes\classes.zip

   Note that <windir> is the folder in which you have Windows 95 or Windows NT 4.0 installed.

Additional query words: 4.00

Keywords : kberrmsg msiew95 msient
Version : WINDOWS:4.0,4.01,5
Platform : WINDOWS
Issue type :