Merge GP tool doesn't recognize one of my point features

[VanessaSimps]

We have had a model builder tool that utilizes the Merge GP tool as a first step in many. This model has been up and running for several years, with out issue (we are actually in ArcMap, but there isn't a forum for that out here anymore...). This tool runs nightly during a maintenance window. 

On Tuesday morning I got an email that the tool didn't run properly. After a bit of investigation of the log files, the Model pooped out on me at the Merge function with: 

I have stepped manually through the merge function with each of the point layers and have identified the one layer that is causing the issue. Here is where my question is. The layer is a point, just like the rest of the features I am trying to merge together. I can't seem to see any issues with it have z, m values (I read to check this in another forum post). I have also exported out all the layers to a fgdb from our Enterprise gdb and ran the check geometry with no errors.  What am I missing?! why would this layer suddenly be causing issues in a tool that has been running successfully for several years? 

[RhettZufelt]

Is there any chance one any of them are now Geometry = Multipoint?

The merge tool recognizes them as different geometries than single point FC's and not allow.

Have you tried using the Merge GP tool to merge that point FC with just one of the other point FC's?

Might give a better idea/message as to what is causing the issue.

R_

[VanessaSimps]

Thanks for the response. Yes, I have manually walked through joining each of the points individually together. So I add two of them, then run. if successfully, I add another and run... and so on. 

I will need to check on the mulitpoint. not sure how that would have happened, but will go take a look and let you know if that was it. 

[VanessaSimps]

Unless I am not looking in the right place, the layer is a regular old Point layer, not multipoint: 

[JeffHouser]

As noted in RhettZufelt's post, if you find that "multipoint" is the source to the problem, maybe you could integrate "explode" to incoming layers prior to merging.

- Jeff

[RhettZufelt]

Hmmm.  Not sure where to go from here.

Have you made a copy of the FC and tried to merge it with the original?  If it can't merge with itself, suspect something is corrupt in the dataset, especially since it just started on it's own.  Have noticed that Repair Geometry doesn't always "fix" things.

R_

[VanessaSimps]

That was a good test! I did what you suggested and the merge back to itself was successful. So at least I know that. I think I will make a call to Esri tech support to help me figure out what I am missing. Thanks for the help and good test ideas!