Thanks Willy & Paul, I've sent the exported tool to the support email, so I guess we'll see what they come back with. Out of interest I tried to change the order of operation within the created tool and it made absolutely no difference!

Obviously (!) the last try was with all Windows Explorer windows shut. I've downloaded Process Explorer - what now?
Here's a shot of the Process Explorer window.

Sorry, I spoke too soon. I created a new tool which OCRed and then converted to PDF/A, called unoriginally "OCR & PDF/A". When I run this tool with both Batch Processing and Multi-Threaded Processing turned on, then I get the same error message when trying to save. Again, here's a scre...

Great, turning on batch processing worked - thanks for the assist...
Peter

Hi there, I'm very new to PDFTools and am trying to add an OCR layer to existing PDF files, so I don't want to rename the files in any way. When I run the tool I get an error message at the end saying "The process cannot access the file because it is being used by another process". I've at...