Okay so this will be a pretty short one, but hopefully help some folks that are upgrading their solutions from SharePoint 2010 to SharePoint 2013.
While developing fields, content types and the likes in SharePoint 2010, there’s always a few good rules and practices to follow. A good rule of thumb that I tend to stick to is to never use any reserved or system-name for your fields that you create. In this quick post I’ll talk about how to fix the "Duplicate field name was found" after you upgrade from 2010 to SharePoint 2013 and try to deploy and activate your feature(s).
In one of my projects that I am involved in, I was tasked to upgrade their existing SharePoint 2010 solutions to SharePoint 2013 – and this is where these problems hit us, hard.
A duplicate field name "Name" was found
If you have upgraded your solution from SharePoint 2010 to SharePoint 2013 and you deploy your code, only to find out that you are getting the notorious error message saying "A duplicate field name ‘fieldname’ was found" you might think you did something wrong in the deployment steps or otherwise failed to successfully upgrade your solution. What actually might have happened is a case of the "don’t use any reserved or system names, please" fever.
After some digging around our 30 projects, I found that the features and finally fields it were complaining about. While investigating the xml here, I noted that the "Name"****was the failing factor. If we changed the Name property to something unique (hence, not a built-in field name), it seems to work out nicely.
Field xml for the SharePoint 2010 project
Field xml for the modified 2013 project, after modification
What’s the difference?
So if you look at the two basic samples above, you can see that the small difference is what’s in the "Name" property. If I changed the value to something unique, it started working immediately.
But, doing this will of course bring up other questions that you need to take into consideration and think about.
- Is there any code reliant on your field’s name property?
- Will it break any functionality in your code or configured lists/views etc?
- What happens to data that potentially will be migrated from the old environment into the new environment? Can you map the data to the correct fields properly?
I thought I’d post this to save someone else from having to spend a few hours digging into the various bits and pieces of an enterprise project to find out where it breaks down after the upgrade. Should you encounter the error message in the title of this post immediately after upgrading your solutions, this may very well be the cause.
Please also make note that this solution is one solution to the problem. Perhaps there’s more solutions available to we can use to fix these issues. Should you know of any such solution, don’t hesitate to comment on the post and I’ll update it and give you the cred :-)
SharePoint Server 2013 is an awesome product that is still uncharted territory for many organizations, but I’m seeing a huge increase in the adoption of 2013 locally and with that we’ll have plenty of time to dig into these fine bits of SharePoint magic :-)