DET File Extension

DET file icon
Sage ACT! 5 Email Message
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    2.2 (4 votes)

What is DET file?

Full format name of files that use DET extension is Sage ACT! 5 Email Message. Sage ACT! 5 Email Message specification was created by Sage. DET files are supported by software applications available for devices running Windows. DET file belongs to the Data Files category just like 1258 other filename extensions listed in our database. The software recommended for managing DET files is Act!. Act! software was developed by The Sage Group plc, and on its official website you may find more information about DET files or the Act! software program.

Programs which support DET file extension

Programs that can handle DET files are as follows. Files with DET extension, just like any other file formats, can be found on any operating system. The files in question may be transferred to other devices, be it mobile or stationary, yet not all systems may be capable of properly handling such files.

Programs that support DET file

Windows Windows

How to open file with DET extension?

There can be multiple causes why you have problems with opening DET files on given system. What is important, all common issues related to files with DET extension can be resolved by the users themselves. The process is quick and doesn’t involve an IT expert. We have prepared a listing of which will help you resolve your problems with DET files.

Step 1. Install Act! software

The main and most frequent cause precluding users form opening DET files is that no program that can handle DET files is installed on user’s system. To address this issue, go to the Act! developer website, download the tool, and install it. It is that easy Above you will find a complete listing of programs that support DET files, classified according to system platforms for which they are available. If you want to download Act! installer in the most secured manner, we suggest you visit The Sage Group plc website and download from their official repositories.

Step 2. Check the version of Act! and update if needed

If the problems with opening DET files still occur even after installing Act!, it is possible that you have an outdated version of the software. Check the developer’s website whether a newer version of Act! is available. Software developers may implement support for more modern file formats in updated versions of their products. The reason that Act! cannot handle files with DET may be that the software is outdated. The most recent version of Act! is backward compatible and can handle file formats supported by older versions of the software.

Step 3. Set the default application to open DET files to Act!

If the issue has not been solved in the previous step, you should associate DET files with latest version of Act! you have installed on your device. 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

  • Choose the Open with entry from the file menu accessed by right-mouse clicking on the DET file
  • Select Choose another app → More apps
  • The last step is to select Look for another app on this PC option supply the directory path to the folder where Act! is installed. Now all that is left is to confirm your choice by selecting Always use this app to open DET files and clicking OK.

The procedure to change the default program in Mac OS

  • Right-click the DET file and select Information
  • Open the Open with section by clicking its name
  • From the list choose the appropriate program and confirm by clicking Change for all....
  • Finally, a This change will be applied to all files with DET extension message should pop-up. Click Continue button in order to confirm your choice.

Step 4. Ensure that the DET file is complete and free of 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 DET file. Being unable to access the file can be related to various issues.

1. The DET may be infected with malware – make sure to scan it with an antivirus tool.

If the DET is indeed infected, it is possible that the malware is blocking it from opening. Immediately scan the file using an antivirus tool or scan the whole system to ensure the whole system is safe. If the DET file is indeed infected follow the instructions below.

2. Ensure the file with DET extension is complete and error-free

Did you receive the DET file in question from a different person? Ask him/her to send it one more time. During the copy process of the file errors may occurred rendering the file incomplete or corrupted. This could be the source of encountered problems with the file. If the DET file has been downloaded from the internet only partially, try to redownload it.

3. Check if the user that you are logged as has administrative privileges.

Sometimes in order to access files user need to have administrative privileges. Log out of your current account and log in to an account with sufficient access privileges. Then open the Sage ACT! 5 Email Message file.

4. Check whether your system can handle Act!

If the systems has insufficient resources to open DET files, try closing all currently running applications and try again.

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 Sage ACT! 5 Email Message file. It may be the case that the DET files work properly with updated software that addresses some system bugs.

Do you want to help?

If you have additional information about the DET 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 DET file.

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