Hi @orb,
This is a limit of the file systems windows uses (NTFS, exFAT, UDF, FAT32)
There is a limit of:
“32,760 Unicode characters with each path component no more than 255 characters” source
In that statement component refers individually to each and every;
- folder name
- separators (backslash \)
- file name and extension including the period
- drive letter including the colon and backslash \
- and a NULL character at the end of it all
So the path itself can be more than 255 but the file name itself (or even a folder name) can only be 255.
Your original name even without an extension is 265 characters long.
inter-individual differences in the electrophysiological characteristics of spindles eg density, amplitude, duration are highly correlated with Reasoning abilities ie fluid intelligence problem solving skills, the ability to employ logic, identify complex patterns
Here are some more references/terms:
All file systems follow the same general naming conventions for an individual file: a base file name and an optional extension, separated by a period. source
Note that a directory is simply a file with a special attribute designating it as a directory, but otherwise must follow all the same naming rules as a regular file. source
The term path refers to one or more directories, backslashes, and possibly a volume name. source
The path to a specified file consists of one or more components, separated by a special character (a backslash), with each component usually being a directory name or file name. source
In editions of Windows before Windows 10 version 1607, the maximum length for a path is MAX_PATH, which is defined as 260 characters. In later versions of Windows, changing a registry key or using the Group Policy tool is required to remove the limit. source
The Windows API has many functions that also have Unicode versions to permit an extended-length path for a maximum total path length of 32,767 characters. This type of path is composed of components separated by backslashes, each up to the value returned in the lpMaximumComponentLength parameter of the GetVolumeInformation function (this value is commonly 255 characters). source
32,760 Unicode characters with each path component no more than 255 characters
source
Hi @AlanG I believe that Explorer is imposing smaller than max values for “our protection” 
, as I tried what you did in the temp folder and while mine got cut off at 240 chars as well, 236 for the name plus 4 for the .txt I was able to get longer file names with some trickery.
I was able to use longer filenames getting up to the full word identify. Here is how.
I created a new file in explorer and tried to name it:
inter-individual differences in the electrophysiological characteristics of spindles eg density, amplitude, duration are highly correlated with Reasoning abilities ie fluid intelligence problem solving skills, the ability to employ logic, identify complex patterns.txt
When I pressed enter the file was truncated to
inter-individual differences in the electrophysiological characteristics of spindles eg density, amplitude, duration are highly correlated with Reasoning abilities ie fluid intelligence problem solving skills, the ability to employ log.txt
I created a second file with the full name (ending patterns.txt)
when I presses enter it gave me a warning that the file existed, indicating it was going to truncate at the same spot, and asked if I wanted to make a file with the same name but also including " (2)" at the end. I chose OK. This gave me a file 4 characters longer:
inter-individual differences in the electrophysiological characteristics of spindles eg density, amplitude, duration are highly correlated with Reasoning abilities ie fluid intelligence problem solving skills, the ability to employ log (2).txt
I then tried making a copy of that file and renaming it the full original name (ending patterns.txt) and it truncated it as
inter-individual differences in the electrophysiological characteristics of spindles eg density, amplitude, duration are highly correlated with Reasoning abilities ie fluid intelligence problem solving skills, the ability to employ logic, identify.txt
Trying to make another file with that same name didn’t give me an option for adding " (2)" it just told me it was a duplicate name and needed a different name.
Here are the names and lengths I was able to get in explorer:
Here are the sizes I was able to create in explorer:
c:\temp\inter-individual differences in the electrophysiological characteristics of spindles eg density, amplitude, duration are highly correlated with Reasoning abilities ie fluid intelligence problem solving skills, the ability to employ log.txt
Path length: 248
Filename length: 240
c:\temp\inter-individual differences in the electrophysiological characteristics of spindles eg density, amplitude, duration are highly correlated with Reasoning abilities ie fluid intelligence problem solving skills, the ability to employ log (2).txt
Path length: 252
Filename length: 244
c:\temp\inter-individual differences in the electrophysiological characteristics of spindles eg density, amplitude, duration are highly correlated with Reasoning abilities ie fluid intelligence problem solving skills, the ability to employ logic, identify.txt
Path length: 260
Filename length: 252
