How To Fix UGMD8010 - Data model cannot be synchronized; see long text

SAP Error Message - Details

• Message type: E = Error

• Message class: UGMD8 - Change Management

• Message number: 010

• Message text: Data model cannot be synchronized; see long text

What causes this issue?

Automatic data model synchronization is <ZH>not possible</> due to the
imminence of serious inconsistency.
This situation can occur, for example, if the compound of one field to
an independent field is to be revoked and the system still contains
<ZH>ambiguous data</> with regards to the compound to be deleted. An
uncontrolled conversion of this data would most likely lead to serious
and unreconcilable inconsistencies.

System Response

The data model synchronizer and the generation of the application area
will be terminated.

How to fix this error?

Manual steps need to be taken before you can proceed with the action in
the data model:
Start by temporarily reversing the decisive change that was made in the
field definition. This is to allow you to relaunch the application on
the basis of the unchanged data model. For example, insert again the
compound of fields that was deleted, and activate the characteristic in
its original state.
Launch the application. Now, <ZH>delete</> all <ZH>ambiguous </>master
data values of the respective field. If you remove a compound, make sure
that, for example, all master data values being retaining have a <ZH>
uniform value for the independent characteristic to be deleted.</>
All other values need to be <ZH>deleted.</> The system will inform you
if these values are still in use. These uses also need to be deleted.
Once you have deleted all ambiguous master data values, repeat the
change to the data model you made earlier (for example, delete the
compound of fields again). If the system no longer reports any potential
data inconsistencies, you should be able to run the data model
synchronizer successfully.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.