Error while trying to merge layers (number of features is zero)

[MiguelJaramillo]

Hi guys, I have around 30 layers (shp) that I want to merge. The process has been to create a merged shapefile and then that merged shapefile gets combined with another layer , and so on.

However, sometimes I get "The number of features in MergedFeatures is zero. Merge Layers failed. "

I am new to ArcGIS online, so I don't know what that means. When I add layers to the map, all of them show successfully 

Can you help me to solve this, please? 

[DavidPike]

How big is this shapefile getting?  I think if the dbf gets to about 2GB it implodes but unsure if AGOL implements the storage a bit differently compared to a SHP sat on a drive.