HDR merge "Internal Error"

[sloppystick]

When I merge photos, I'm able to see an HDR preview. Then I hit merge, and it stops about halfway through and says "An internal error has occurred." I've tried uninstalling Lightroom and reinstalling it, but I'm still getting the same error. I've also tried several different bracketed photos. I'm using the same external hard drive with no problem on my old PC, but I keep getting this error on my new iMac. Please help!

[Bob Somrak]

Take the comma out of the folder path and see if it works.  Windows may allow that but Apple and/or Lightroom might not when using HDR. 

[sloppystick]

I tried to merge 3 photos in a folder with no commas, but I'm still getting the same error.

[Bob Somrak]

I replied a little while ago with a different idea.  Try WRITING to that drive on the mac.  If thats not it I am out of ideas

[Bob Somrak · Accepted solution]

Another issue is if the External Drive is formatted with NTFS (Windows) than the Mac and READ this drive but not WRITE to it unless you use software drivers that allow this.  Here is more info   How to Write to NTFS Drives on a Mac  

[sloppystick]

I think you might be right on the NTFS issue. I was using this same external drive for my windows laptop before I bought my Mac. I'll read more into this to see how I can fix it without reformatting and losing all my photos. I'll update once I do that. Thanks for your help.

[sloppystick]

You were correct on the NTFS issue. Everything is good now, even with the commas. Thanks again!