If you're like the vast majority of computer users around the world, it's likely that your device is running a Windows operating system, which has been the dominant force in this field for decades. If you use your computer sufficiently, you may have encountered some issues when naming new files or renaming existing ones, as the system informs you of the invalidity of your choice for certain characters.
When attempting to name a new file or rename an existing one, you may hear a warning sound and see a small bubble notifying you that the use of certain symbols is not allowed, such as / ? If you're a seasoned computer user, you've likely faced this issue before. In this article, we will explain why using certain symbols in file names is not possible.
9 Symbols Prohibited for Use in File Names on Windows
There are 9 symbols prohibited for use in file names on the Windows system, as these characters are reserved for other uses in the file system, and they are as follows:
: \ / : ? ” < > |
Each of these symbols has a specific reason for being prohibited when used in file or folder names, and we will go through each one to determine the rationale behind it.
Symbol / or “backslash”
This character is primarily banned because it's used in file paths within the Windows system, where the character acts as a delimiter between folder names. For example, if you have a text file named file.txt inside a folder named example within a folder named root folder on drive C, the file path would be:
C:\root folder\example\file.txt
Now, if you decide to name the file file \example.txt, the file path would be:
C:\root folder\example\file\example.txt
This poses a problem as the system reads only the existence of a file named example.txt and assumes the presence of a folder named file, which may not actually exist.
Symbol / or “Forward Slash”
There are two reasons to prevent the "/" character from being used in file names, the first and most important is that it is used in system-specific commands, and the second is that it is used in web addresses, where it acts as a separator between subsections within sites. Since Windows allows adding shortcut files to websites, the use of the "/" character in file names has been prohibited.
Symbol ? * or question mark and asterisk
These two icons have very similar uses in reality, as each can replace the rest of the text in searches within the Windows system. Simply put, you can use an asterisk (*) to substitute any combination of letters or numbers. For example, you can search for a file whose name you know the beginning of by entering something like "file??. png" within the search box. Similarly, an asterisk (*) can be used to search for any files with a specific suffix. For example, if you enter "*.docx", all Word documents are displayed in the folder, and if you enter "*.ai", design files made by Adobe Illustrator will be displayed.
Symbol ” or quotation mark
This code is blocked because it allows spaces in file and folder names, where the space in path names is used to emphasize that the entire path points to a file or folder and not two separate parts. Although a quotation tag is not always necessary in path names, this code is assigned to cases that include spaces, to clearly identify it for this purpose.
Symbol : or colon
As in the use of \ in file names, the exclusive use of this symbol is in disk names in Windows. In this context, disks are labeled with letters followed by colons, such as E: or C: and so on, so the code is prevented from being used in any other file name.
The <> symbol or the greater and lesser symbol and the | symbol
In normal circumstances, these symbols may not be visible, making it challenging for users to discern their significance. However, when using the command prompt, it becomes clear why these symbols are prohibited in file names. The <> symbols are used to indicate redirecting a program's output to another file or another program's input.
The | symbol serves as a direct method for communication between programs, directing the output of the first program directly into the input of the second.
Modern systems can bypass most restrictions on character usage since they are not associated with specific meanings except for a very limited number. Some rules apply unevenly, such as allowing the use of a period, which serves as a system mechanism to distinguish between a file name and its extension.
Although modern systems may permit this, there were and still are limitations that were in place previously. The primary reason for these restrictions is to ensure support continuity and avoid unnecessary issues. Current system files often do not work on previous systems, and therefore, it is advisable to refrain from allowing these characters to prevent unnecessary problems.
Why do many characters remain restricted without a compelling reason?
Despite the ability of modern systems to overcome most restrictions on character usage, some rules are applied unevenly. For instance, a period is allowed as a system mechanism to differentiate between a file name and its extension. If this approach were consistently applied, it would be possible to add two periods anywhere.
In general, there is a fundamental reason for maintaining these previous restrictions, namely to ensure support continuity and avoid potential issues. Current system files often do not align with previous systems, and as a result, it is preferable to restrict the use of these characters to prevent unnecessary problems.
