PHO File Extension

PHO file icon
Gerber Photoplot Format
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What is PHO file?

Full format name of files that use PHO extension is Gerber Photoplot Format. Gerber Photoplot Format specification was created by Ucamco. Files with PHO extension may be used by programs distributed for Windows platform. Files with PHO extension are categorized as CAD Files files. The CAD Files subset comprises 158 various file formats. The most popular program for handling PHO files is ViewMate, but users can choose among 1 different programs that support this file format.

Programs which support PHO file extension

Programs that can handle PHO files are as follows. Files with PHO 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 PHO file

How to open file with PHO extension?

Being unable to open files with PHO extension can be have various origins. What is important, all common issues related to files with PHO 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 PHO files.

Step 1. Install ViewMate software

Install software to open PHO file The main and most frequent cause precluding users form opening PHO files is that no program that can handle PHO files is installed on user’s system. This one is an easy one. Select ViewMate or one of the recommended programs (for example, Altium Designer) and download it from appropriate source and install on your system. Above you will find a complete listing of programs that support PHO files, classified according to system platforms for which they are available. The safest method of downloading ViewMate installed is by going to developer’s website () and downloading the software using provided links.

Step 2. Verify the you have the latest version of ViewMate

Update software that support file extension PHOIf the problems with opening PHO files still occur even after installing ViewMate, it is possible that you have an outdated version of the software. Check the developer’s website whether a newer version of ViewMate 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 PHO files are not compatible with ViewMate. All of the file formats that were handled just fine by the previous versions of given program should be also possible to open using ViewMate.

Step 3. Associate Gerber Photoplot Format files with ViewMate

If you have the latest version of ViewMate installed and the problem persists, select it as the default program to be used to manage PHO 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 PHO file on Windows

The procedure to change the default program in Windows

  • Right-click the PHO file and choose Open with option
  • Next, select the Choose another app option and then using More apps open the list of available applications
  • To finalize the process, select Look for another app on this PC entry and using the file explorer select the ViewMate installation folder. Confirm by checking Always use this app to open PHO files box and clicking OK button.
Associate software with PHO file on Mac

The procedure to change the default program in Mac OS

  • Right-click the PHO file and select Information
  • Open the Open with section by clicking its name
  • Select ViewMate and click Change for all...
  • If you followed the previous steps a message should appear: This change will be applied to all files with PHO extension. Next, click the Continue button to finalize the process.

Step 4. Verify that the PHO is not faulty

If you followed the instructions form the previous steps yet the issue is still not solved, you should verify the PHO file in question. Being unable to access the file can be related to various issues.

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

If the PHO is indeed infected, it is possible that the malware is blocking it from opening. It is advised to scan the system for viruses and malware as soon as possible or use an online antivirus scanner. If the scanner detected that the PHO file is unsafe, proceed as instructed by the antivirus program to neutralize the threat.

2. Check whether the file is corrupted or damaged

If the PHO file was sent to you by someone else, ask this person to resend the file to you. It is possible that the file has not been properly copied to a data storage and is incomplete and therefore cannot be opened. If the PHO file has been downloaded from the internet only partially, try to redownload it.

3. Verify whether your account has administrative 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 Gerber Photoplot Format file.

4. Make sure that the system has sufficient resources to run ViewMate

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

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

Latest versions of programs and drivers may help you solve problems with Gerber Photoplot Format files and ensure security of your device and operating system. Outdated drivers or software may have caused the inability to use a peripheral device needed to handle PHO files.

Do you want to help?

If you have additional information about the PHO 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 PHO file.

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