Question: I have a C# application using Oracle database and Entity Framework 5. Oracle client is version 12c R1. My application uses database first approach. I'm trying to run the app using Visual Studio Enterprise 2015. When I access the edmx file and I try to update the model from the database, it gives me the following error:

> 
> An exception of type 'System.ArgumentException' occurred while attempting to update from the database. The exception message is: 'Unable to convert runtime connection string to its design-time equivalent. The libraries required to enable Visual Studio to communicate with the database for design purposes (DDEX provider) are not installed for provider 'Oracle.DataAccess.Client'. Connection string: XXXXX.
> 
> 
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This error does not occur when I use Visual Studio Ultimate 2013. Only on Visual Studio Enterprise 2015.

Is there any known incompatibility issue with the new one?

Answer: 
I believe it is because not yet out ODT version compatible with Visual Studio 2015. Wait or will have no choice for now?

[Oracle Developer Tools](http://www.oracle.com/technetwork/developer-tools/visual-studio/overview/index.html)
I installed the Oracle Developer Tools for 2015 but still could not get this to work. When I would attempt to do an Update Model from Database with Entity Framework, I encountered this error below.

[![enter image description here](https://i.stack.imgur.com/tKQM6.jpg)](https://i.stack.imgur.com/tKQM6.jpg)

So I did as instructed and removed all references to Oracle from the GAC, even following advice here [Oracle .Net Developer's Guide](https://docs.oracle.com/cd/E11882_01/win.112/e23174/InstallODP.htm#ODPNT152), but it still didn't work. Being that I'm on a tight schedule and don't have time to fool with this, I opened my solution in VS2012, did my Entity Framework changes, and then reopened the solution in VS2015, and that worked fine. Irritating, but at least I have a workaround for now.