Mosaic to New Raster tool fail

Question

I'm trying to merge 24 DEM files,

after applying the tool (Mosaic to New Raster) only 11 out of the 24 merged.

All the original files are in the same projection, pixel type, band, etc. I also tried DEM to raster tool first before using Mosaic to New Raster and the results were the same. I'm using 10.2 Standard without any additional extensions.

AliciaShyu_Love · Accepted Answer

Apparently the tool worked but somehow it doesn't display right. If I zoom in on the on the gaps I can see the raster, but once I zoom out to full extent I still see the gaps.