"Not enough space on the default volume"

[Remo Nonaz]

I'm trying to do a four image merge to 'HDR Pro in Photoshop' from Lr4. When I do this I get the error message, 'There is not enough space on the default volume to complete this operation'. I tried cutting back to three images and got the same error message, though this process has worked with three images before. I checked the preferences>performance settings and I have 7175MB of RAM available and over 400GB of scratch disk space. I searched the web with the error message in quotes and found no posts or comments closely related to the problem.

Any ideas what this is and how it is resolved?

[Tony Jay]

Remo, I think the message may refer to hard drive storage space.
Ps doesn't have enough space on the hard drive to put the merged image.

Regards

Tony Jay

[Remo Nonaz]

...except that I checked my primary (F) photo hard drive where I store images and it still has over half a TB of available space. I know 32-bit HDR images can be large, but not THAT large 

[Remo Nonaz]

OK. I figured it out. I had two drives checked for use; C and F. C is a small system SSD with only a little room left. F is a 1.5TB rotational drive with 400GB available. I shut off the C drive leaving Ps only the big rotational drive to write to and the problem went away.