The CIL generator found errors and could not save the new assembly.

The CIL generator found errors and could not save the new assembly.
There are two possible solution:

1. Light one, which does not require a lot of time.
Usually you will see CIL compilation error in Compiler output. Something like that:
CIL generation: Line Number 90 - Line Number 99 - Method MethodName in Type ObjectName was not found in the CIL that was generated from X++.
But method exists. Try following:
- Right click the object and Restore it
- Compile the object
- If object is a part of class hierarchy, compile forward from first parent.
- Run Generate incremental CIL again


2. Another time consuming solution which helps in all other cases:
- Stop AX services
- Delete all files from below path (Delete only files which are not in any folder)
C:\Program Files\Microsoft Dynamics AX\60\Server\ServerName\bin\XppIL
- Start AX service
- Synchronize Data Dictonary
- Full Compile
- Full CIL Compile

These all operation must be perform in the same sequence.
Try to reopen your AX client. It should work.

One more location to clean up IL completely is the SysXppAssembly table ( http://msdn.microsoft.com/en-us/library/sysxppassembly.aspx)

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