Description
As Electric Make (eMake) has evolved, so has the eMake history file format. Though CloudBees attempts to maintain backwards compatibility such that history files produced by older versions of eMake can be used with newer versions of eMake, occasionally incompatible changes are required. To avoid attempts to use incompatible history files, the history file contains a version number, which eMake validates when it first reads the file. If the history version is not one that eMake can support, the history is considered invalid.
Reasons
This message is displayed if you attempt to run a build with an incompatible history file. This is most likely to occur when you have recently upgraded to a new version of eMake.
Fixes
Verify that you are using the correct history file. Elaborate history file management systems introduce the possibility of accidentally using the wrong history file for the build.
If you verified you are using the correct history file, generate a new history file for the build using the new version of eMake. This is the surest way to get a good history file again.
If generating a new history file is not practical, it may be possible to convert the old history file to a newer format. Contact CloudBees technical support for assistance if this type of conversion is required.