CU_ file icon

CU_ File Extension

Microsoft Windows Winhelp Compressed
  • Developer
    Microsoft Corporation
  • Category
    Archive Files
  • Popularity
    3 (2 votes)

What is CU_ file?

CU_ is a file extension commonly associated with Microsoft Windows Winhelp Compressed files. Microsoft Windows Winhelp Compressed specification was created by Microsoft Corporation. Files with CU_ extension may be used by programs distributed for Windows platform. Files with CU_ extension are categorized as Archive Files files. The Archive Files subset comprises 619 various file formats. Microsoft Windows is by far the most used program for working with CU_ files. Microsoft Windows software was developed by Microsoft Corporation, and on its official website you may find more information about CU_ files or the Microsoft Windows software program.

Programs which support CU_ file extension

The following listing features CU_-compatible programs. Files with CU_ suffix can be copied to any mobile device or system platform, but it may not be possible to open them properly on target system.

Programs that support CU_ file

How to open file with CU_ extension?

Being unable to open files with CU_ extension can be have various origins. Fortunately, most common problems with CU_ files can be solved without in-depth IT knowledge, and most importantly, in a matter of minutes. The list below will guide you through the process of addressing the encountered problem.

Step 1. Get the Microsoft Windows

Install software to open CU_ file Problems with opening and working with CU_ files are most probably having to do with no proper software compatible with CU_ files being present on your machine. The solution to this problem is very simple. Download Microsoft Windows and install it on your device. Above you will find a complete listing of programs that support CU_ files, classified according to system platforms for which they are available. If you want to download Microsoft Windows installer in the most secured manner, we suggest you visit Microsoft Corporation website and download from their official repositories.

Step 2. Check the version of Microsoft Windows and update if needed

Update software that support file extension CU_If the problems with opening CU_ files still occur even after installing Microsoft Windows, it is possible that you have an outdated version of the software. Check the developer’s website whether a newer version of Microsoft Windows is available. Software developers may implement support for more modern file formats in updated versions of their products. This can be one of the causes why CU_ files are not compatible with Microsoft Windows. All of the file formats that were handled just fine by the previous versions of given program should be also possible to open using Microsoft Windows.

Step 3. Set the default application to open CU_ files to Microsoft Windows

If you have the latest version of Microsoft Windows installed and the problem persists, select it as the default program to be used to manage CU_ 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.

Associate software with CU_ file on Windows

The procedure to change the default program in Windows

  • Right-click the CU_ file and choose 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 Microsoft Windows installation folder. Confirm by checking Always use this app to open CU_ files box and clicking OK button.
Associate software with CU_ file on Mac

The procedure to change the default program in Mac OS

  • Right-click the CU_ file and select Information
  • Proceed to the Open with section. If its closed, click the title to access available options
  • Select Microsoft Windows and click Change for all...
  • If you followed the previous steps a message should appear: This change will be applied to all files with CU_ extension. Next, click the Continue button to finalize the process.

Step 4. Ensure that the CU_ file is complete and free of errors

Should the problem still occur after following steps 1-3, check if the CU_ file is valid. Being unable to access the file can be related to various issues.

Check CU_ file for viruses
1. Check the CU_ file for viruses or malware

Should it happed that the CU_ is infected with a virus, this may be that cause that prevents you from accessing it. Scan the CU_ file as well as your computer for malware or viruses. If the scanner detected that the CU_ file is unsafe, proceed as instructed by the antivirus program to neutralize the threat.

2. Check whether the file is corrupted or damaged

Did you receive the CU_ 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. It could happen the the download process of file with CU_ 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

Some files require elevated access rights to open them. Switch to an account that has required privileges and try opening the Microsoft Windows Winhelp Compressed file again.

4. Verify that your device fulfills the requirements to be able to open Microsoft Windows

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

5. Verify that your operating system and drivers are up to date

Regularly updated system, drivers, and programs keep your computer secure. This may also prevent problems with Microsoft Windows Winhelp Compressed files. It may be the case that the CU_ files work properly with updated software that addresses some system bugs.

Do you want to help?

If you have additional information about the CU_ 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 CU_ file.

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