Thank you for your post.
I am unable to replicate the issue using FileMaker Pro 15.0.1 under both Windows 7 and Mac OS X 10.11.6. Here are the steps I took:
1. I created a file "Test.fmp12" that contains a Container field "Container".
2. I added one record, and inserted the file "Test_1.fmp12".
3. I created a script "TEST" with the following script steps:
Set Variable [ $file ; Value: "file:" & Get (DesktopPath) & GetContainerAttribute ( Container ; "filename" ) ]
Export Field Contents [ Container ; "$file" ]
Show Custom Dialog [ Get ( LastError ) ]
4. I put "Test_1.fmp12" on the Desktop and opened it in FileMaker Pro 15.
5. I returned to "Test.fmp12" and executed the script.
6. I get an error that it can't be created, and when I click OK to dismiss the dialog box, I get the Custom Dialog showing Get ( LastError ) = 800.
7. I closed Test_1.fmp12, and moved it to a network drive. I opened the file on the network drive.
8. I changed the Set Variable script step and replaced "Get (DesktopPath)" with the full network drive path.
9. I executed the script, and I get the same error.
Let me know what I am doing differently than you so I can replicate the issue.
I am specifically using PDF files in the container and filewin: for the
path. Otherwise, the script looks similar to mine.
When PDF files are opened, they are loaded into memory. The original file can be overwritten at any time. When you save the opened PDF, then it will overwrite the original file. This is why you are not getting an error message.