cannot save bitmap "Bitmap I/O Error"

[mikeumrsub]

I am using Adobe Substance as a material generator using a Poliigon .sbsar file.  When I try exporting the bitmap I get an error message.  "Cannot save bitmap 'C:/......'

Any ideas?  I am new to this software but it did work the first time I used it.

[John Krumpotick]

I got that once when I tried exporting the bitmaps to the same folder the SBSAR was in, could that be it?