The type exists in both 'x.dll' and 'x.dll'

Question

In Visual Studio in Immediate Window I was trying to check for value of variable:

(listElem as Project).ID

and I get error

The type 'projName.Folder.Project' exists in both 'projName.dll' and 'projName.dll'.

How can that be?

EDIT: The 'projName.dll' is the dll I am debugging, so there is no reference of 'projName.dll' added to 'projName.dll'. In bin folder I have only one 'projName.dll'.It's not web app.

Are you referencing multiple copies of the same assembly (in different folders)? — Jeff Mercado, Jan 22 '17 at 19:15
Possible duplicate of [ASP.Net error: "The type 'foo' exists in both "temp1.dll" and "temp2.dll"](http://stackoverflow.com/questions/371426/asp-net-error-the-type-foo-exists-in-both-temp1-dll-and-temp2-dll) — Matthew Cawley, Jan 22 '17 at 19:24

score 0 · Answer 1 · answered Jan 22 '17 at 19:15

I've run into this exact issue before. You likely have multiple copies of the same dll (potentially different versions) in your references or bin folder. Look for duplicates in both of these locations and remove them.

The type exists in both 'x.dll' and 'x.dll'

1 Answers1