DTD File Extension

DTD file icon
Document Type Definition Format

What is DTD file?

DTD is a short form of Document Type Definition and this file type is actually a text file which contains information about the elements that are used by XHTML, HTML, XML or SGML files.

The data saved in DTD file tell us about the structure of the document with which it is associated which may include nesting and order of the elements which are introduced in the specific document. DTD files ensure the uniformity of the specific file when that specific file is transmitted from one computer to another. In some cases DTD file can also tell about validity of specific document.

Programs which support DTD file extension

Below you will find an index of software programs that can be used to open DTD files divided into 3 categories according to system platform supported. DTD files can be encountered on all system platforms, including mobile, yet there is no guarantee each will properly support such files.

How to open file with DTD extension?

Being unable to open files with DTD extension can be have various origins. Fortunately, most common problems with DTD files can be solved without in-depth IT knowledge, and most importantly, in a matter of minutes. The following is a list of guidelines that will help you identify and solve file-related problems.

Step 1. Install XMLSpy software

Problems with opening and working with DTD files are most probably having to do with no proper software compatible with DTD files being present on your machine. This issue can be addressed by downloading and installing XMLSpy or different compatible program, such as EditiX, Windows Notepad, Microsoft Visual Studio. The full list of programs grouped by operating systems can be found above. One of the most risk-free method of downloading software is using links provided by official distributors. Visit XMLSpy website and download the installer.

Step 2. Check the version of XMLSpy and update if needed

If you already have XMLSpy installed on your systems and DTD files are still not opened properly, check if you have the latest version of the software. It may also happen that software creators by updating their applications add compatibility with other, newer file formats. This can be one of the causes why DTD files are not compatible with XMLSpy. The latest version of XMLSpy should support all file formats that where compatible with older versions of the software.

Step 3. Associate Document Type Definition Format files with XMLSpy

After installing XMLSpy (the most recent version) make sure that it is set as the default application to open DTD files. The process of associating file formats with default application may differ in details depending on platform, but the basic procedure is very similar.

The procedure to change the default program in Windows

  • Clicking the DTD with right mouse button will bring a menu from which you should select the Open with option
  • Click Choose another app and then select More apps option
  • To finalize the process, select Look for another app on this PC entry and using the file explorer select the XMLSpy installation folder. Confirm by checking Always use this app to open DTD files box and clicking OK button.

The procedure to change the default program in Mac OS

  • Right-click the DTD file and select Information
  • Find the Open with option – click the title if its hidden
  • Select XMLSpy and click Change for all...
  • A message window should appear informing that This change will be applied to all files with DTD extension. By clicking Continue you confirm your selection.

Step 4. Check the DTD for errors

You closely followed the steps listed in points 1-3, but the problem is still present? You should check whether the file is a proper DTD file. It is probable that the file is corrupted and thus cannot be accessed.

1. Verify that the DTD in question is not infected with a computer virus

If the file is infected, the malware that resides in the DTD file hinders attempts to open it. Scan the DTD file as well as your computer for malware or viruses. If the DTD file is indeed infected follow the instructions below.

2. Check whether the file is corrupted or damaged

Did you receive the DTD file in question from a different person? Ask him/her to send it one more time. It is possible that the file has not been properly copied to a data storage and is incomplete and therefore cannot be opened. It could happen the the download process of file with DTD extension was interrupted and the file data is defective. Download the file again from the same source.

3. Ensure that you have appropriate access rights

There is a possibility that the file in question can only be accessed by users with sufficient system privileges. Log out of your current account and log in to an account with sufficient access privileges. Then open the Document Type Definition Format file.

4. Check whether your system can handle XMLSpy

The operating systems may note enough free resources to run the application that support DTD files. Close all running programs and try opening the DTD file.

5. Check if you have the latest updates to the operating system and drivers

Up-to-date system and drivers not only makes your computer more secure, but also may solve problems with Document Type Definition Format file. It may be the case that the DTD files work properly with updated software that addresses some system bugs.

Do you want to help?

If you have additional information about the DTD file, we will be grateful if you share it with our users. To do this, use the form here and send us your information on DTD file.

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