Error when importing CRM solution 0x8004F658: The label {}, id: {} already exists. Supply unique labelid values.

I usually don’t post on CRM bugs but this one made me lose so much time that I figured I might share my experience.

We are in the middle of a CRM 2013 upgrade project and while transporting our main solution with all the entities we keep getting this error message: The label '{0}', id: '{1}' already exists. Supply unique labelid values while importing entity forms. I first thought that somehow we messed up the labels since we have a bilingual English and French system. However, after looking at the LocalizedLabel tables I could not find any duplicates of what the error message was talking about.

Then I decided to do a search in all the system forms in the target environment and check where the labelid occurred. I never really found a duplicate but I noiticed that in some cases the label already existed in the target environment in the formXML. This was as expected but to get over the problem I deleted the problematic forms in the target environment (since they will get overwritten by the new solution anyway). Some forms were the system forms so I could not really delete them, therefore I just stripped them down completely to remove all tabs, sections and fields as much as possible to make sure the custom labels would have been deleted.

Now I publish all the customizations and try importing again. Half of the failures are gone but I still get the same error message on some entity forms. I find it weird since the “duplicate” labels are nowhere to be found. I also validated that in my custoizations.xml the labelid was not duplicated, no, each GUID appeared only once.

With no time to call Microsoft support I had to find a work-around. So here’s what I do (not proud of the solution but it got me out of trouble). I open the customizations.xml file and locate the labelid which solution import is complaining about. And I simply generate a new GUID and replace it:

In some other cases there was not even a “labelid” attribute on the tab so I just added it with a new Guid. This happened in some tab, section and cell nodes, it was all over the place for some reason.

So after assigning a new Guid to all these sections I was able to import successfully. I never really had the time to go deeper into the root cause, but after talking to a colleague we suspect that the issue stems from the fact that we used the “Merge Forms” button that is available in CRM 2013 to help you upgrade your forms. The issue only occurred for the entities for which we used that feature so therefore our suspicion.

I will never be sure but I will try to avoid using that button until I have time to get back to the root cause analysis of this issue, lot of time wasted.