Why does LAMBDA function return #NAME?

Occasional Contributor

i created a LAMBDA function in name manager.


Name: MyLamb

Refers To: =LAMBDA(a, a+99)


Then i enter onto sheet: =MyLamb(5) The cell displays: #NAME?


What's the problem? thx

10 Replies
The recently launched LAMBDA doesn't works with older version of Excel,,, hope you are using either Office 365 or Office Insider !!

Yes, i have Office 365 with free Developer license. LAMBDA doesn't appear in the built-in function list, but if i start typing formula in a cell, it comes up. 




Use this Link...  or  this one also,,, or check this, all are useful to learn more about LAMBDA More on LAMBDA !! 


I think the functionality still requires the Beta Channel 



Something else you could try is to avoid the excursion to Name Manager, which can easily conceal typing errors, and just use


on the worksheet without any naming.  A rather more complicated test involves applying a local name within the cell by using the LET function

= LET(myLambda, LAMBDA(a,a+99), myLambda(5))


@Peter Bartholomew i think i'm not eligible for beta.




Any idea when LAMBDA is coming out of beta?


I don't think it is a question of being ineligible.  It is more a question that access through enterprise licenses is set by IT management.  If you are IT management that still leaves you with a problem to solve!

I wouldn't like to guess a timescale.  The new functionality is revolutionary in terms of how one might go about the creation of Excel solutions, but the development environment is immature and there are severe limitations on the permitted depth of recursion.

@Sergei Baklan 

Are you able to assist with the license problem; time to acknowledge I am out of my depth.

@Peter Bartholomew 

I'm not sure how may I help. No additional Office licenses is required, what is required that's administrative rights, at least on machine.

I do not recommend to install beta as main version, even if it's stable enough. Main issue is compatibility  working in corporate environment. 

How I do - on my office machine I'm on Current channel, virtual (Hyper-V) machine is installed on the same computer and on it with Office Deployment Tool Beta channel is installed. Office is under the same license since 365 subscription allows to install it on few computers for the same user. The only with such solution is licensing of Windows on VM is required. Any license for non-commercial use works, this is not for business. That's better to ask local IT what they could suggest.

On my home machine main (and the only one) is Beta channel, I see no problems working on it. It could be under the same corporate Office 365 subscription.


When it'll be in production - nobody knows. My understanding of the situation is that with current lambdas Microsoft only touch the water collecting feedback from insiders. After that it shall be mockup of lambdas production version. Hope within few months. This version also will be tested on insiders channels first. More complex functionality more time that takes. Time frame also depends on current priorities. I guess another few months, at least. Next is production, channel by channel. So, not in nearest future. Will be happy if I'm wrong.


In general roadmap is here Microsoft 365 Roadmap | Microsoft 365, nothing about lambdas in it. On the other hand it's not well supported.

i am the admin, under the free Developer License.

I found a few ways to enable the beta channel: gpedit, registry...


But if i later revert back to current, would it be a clean rollback? Or will my system get polluted by the beta?



Yes, there are several ways to switch from one channel to another. All work, but which to use depends on your scenario of work. You may switch on any available channel at any time. From semi-annual to beta, from beta back on current, etc. No problems with that.


<Or will my system get polluted by the beta?>

I like it.  Only I think of it as an acceptable dynamic array solution being polluted by legacy practices that I am only too glad to see the back of.