Sunday, June 1, 2014

Visual Studio Add-in creation tips : Build Error.Unable to delete dll file

Problem :

I was working on an add-in in visual studio where it gave me the above error from the second time onward while building the add-in project. As I searched about the issue, it seemed some other process is being locking the dll file of my add-in.

I made sure that all other projects which are using the add-in are closed but it didn't fix the issue. I even turned the virus guard off since they too may cause some issues like this.So, I manually went to the bin folder of where the add-in project is created and deleted the dll file. then onward the build was successful. but this is only until I close the add-in project in visual studio. once I restart, make some changes and rebuild, the error pops up again is this a bug or is there a way to fix this issue?

Solution : 

What cause this issue may be your Visual Studio run the add-in when your Visual Studio is started. You can disable Add-ins (e.g. “Tools” | “Add-in Manager”) and run “devenv.exe /safemode”. 

When I start visual studio the add-in runs automatically.This happens because while creating the add-in using the wizard, I checked 'Microsoft Visual Studio 2010' as an application host and then in the next step i too have checked the option saying that I would like to load the Add-in when the host application starts (see the image below). So, automatically, if another project or a website is running at the moment when I tried to modify the add-in in another instance, the add-in project file is getting locked.