KB170034368: Automation Engine - Prepare for Viewer fails with "Failed to copy" or "BG_ECouldNotOpenFile: The system cannot find the path specified. (Fatal error)"

Summary

Prepare for Viewer fails with:

"ERROR: Failed to copy XXX to YYY"

Or

"PYROUT-0-Unhandled Exception: Exception of class 
BG_ECouldNotOpenFile raised at line 196 of file 
"BGTypes/Private/Source/bg_tfile.cpp"

Additional message:
BG_ECouldNotOpenFile: The system cannot find the path specified.

...

ERROR: Fatal error"

Symptoms

The UNC of the eventual view file(s) is too long (longer than the Windows UNC path limit (255 characters)). 

For instance, for a file:

\\problemlog-gent.esko-graphics.com\CC-SW-Problemlog-Gent\EA280000-EA280999\EA280869\Some_Folder_Name\A_file_with_an_even_longer_filename_to_trigger_Prepare_for_Viewing_error.tif

the eventual view file UNC becomes: 

\\problemlog-gent.esko-graphics.com\CC-SW-Problemlog-Gent\EA280000-EA280999\EA280869\Some_Folder_Name\.view\A_file_with_an_even_longer_filename_to_trigger_Prepare_for_Viewing_error.tif\1\A_file_with_an_even_longer_filename_to_trigger_Prepare_for_Viewing_error.xml

A view folder + viewfile version folder + filename folder is added, which can drastically increase the UNC length. 

Apparently two different situations cause two different errors: 

1. The first file to be rendered fails because of this situation:
   The task fails with:

   PYROUT-0-Unhandled Exception: Exception of class BG_ECouldNotOpenFile
   raised at line 196 of file "BGTypes/Private/Source/bg_tfile.cpp
   Additional message: BG_ECouldNotOpenFile: The system cannot find the path specified.
   Additional data: \\problemlog-gent.esko-graphics.com\CC-SW-Problemlog-Gent\EA280000-EA280999\EA280869\Some_Folder_Name\.view\A_file_with_an_even_longer_filename_to_trigger_Prepare_for_Viewing_error.tif\1\A_file_with_an_even_longer_filename_to_trigger_Prepare_for_Viewing_error.xml
   Stack trace: [1] <unnamed> in BGTypes/Private/Source/bg_tfile.cpp at line 196
   in file "pyroutbltin"
   ERROR: Fatal error"

   See FirstSeparation.log

2. First file(s) can be rendered OK, one of the later separations fails because of this:
   The task fails with: 

   ...
   Progress: 80%
   Progress: 85%
   Progress: 90%
   Progress: 95%
   Progress: 100%
   PYROUT-0-DupDigFilms outdir=\\problemlog-gent.esko-graphics.com\CC-SW-Problemlog-Gent\EA280000-EA280999\EA280869\Some_Folder_Name\.view\A_file_with_a_short_filename.tif\1\ outnam=A_file_with_a_short_filename
   ERROR: Failed to copy \\problemlog-gent.esko-graphics.com\CC-SW-Problemlog-Gent\EA280000-EA280999\EA280869\Some_Folder_Name\.view\A_file_with_a_short_filename.tif\1\A_file_with_a_short_filename.xml to \\problemlog-gent.esko-graphics.com\CC-SW-Problemlog-Gent\EA280000-EA280999\EA280869\Some_Folder_Name\.view\A_file_with_an_even_longer_filename_to_trigger_Prepare_for_Viewing_error - Copy.tif\1\A_file_with_an_even_longer_filename_to_trigger_Prepare_for_Viewing_error - Copy.xml"
   

   See LastSeparation.log

Solution

Use a shorter File and/or Folder name.