limit on number of characters in filename used to oen a document?

Yes. Word (and other Office applications) have a limit on the total length of the full path plus file name (including the extension) when opening or saving files.

From the documentation:

• For Word, PowerPoint, and Access, the total length of the path and file name (including extension) must not exceed 259 characters.
• For Excel, the total length must not exceed 218 characters.

This total includes:

• The drive specification (for example, C:\ – 3 characters)
• All folder names in the path
• The backslashes between folders
• The file name and its extension

If a Documents.Open call in VBA uses a path that exceeds this limit, Word can fail to open the document and may show errors such as:

• Filename is not valid.
• The file could not be accessed.
• The path you entered, 'filename', is too long. Enter a shorter path.

To resolve the issue for long paths in VBA:

• Shorten the file name, and/or
• Move the document to a folder with a shorter path, and/or
• Rename one or more folders in the path to shorter names.

Then update the path used in the Documents.Open statement so that the total length is within the limit.

References:

• You receive an error message when you try to open an Office document
• Error message when you open an Office file that has a long folder name