While searching for an answer to the question - How to open the OPN file? - you probably found websites, which offer software that was able to open any file extension. Do not be fooled, there is no one program that will allow you to work with any file extension, including the OPN file. Each program contains a different type of data and you need specialized software to properly work with the OPN file. Here is a list of programs that are designed to work with the OPN file - remember, these applications are able to open at most a few file extensions, they are designed to work with a specific data type.
| File type | Court Opinion |
| Developer | Lack of information |
| Popularity | |
| Share |
If after installing the program from a list, you still cannot open a file with the OPN extension, the reason may be that the file is damaged. The solution may be to find a new copy of the OPN file you want to open
In this case, the easiest way is to use the tool built into the operating system for association of the OPN file with applications to support it. Double click on the file you cannot open - the operating system will display a list of programs that are likely to work with your OPN file. Choose one of them, or select the location on a disk where you installed one of the applications from our list. Windows should then open the OPN file using the program installed earlier.
Entries containing links of the OPN file extensions with applications is located in the HKEY_CLASSES_ROOT. If you do not know how to get to the Windows Registry, or how to make changes in it, ask a specialist for help. Lack of knowledge on the subject may cause irreversible changes on your computer.
There may be a situation when a computer virus passes itself off as the OPN file. In this case, such a file will definitely not be opened. Download a good antivirus program and scan the OPN file mentioned. If the antivirus application detects malicious data, it may signify that the OPN file is infected.
| OPD | Durango Interferometry Software Document Format |
| OPUS | Opus Audio Format |
| OPAX | Microsoft Office Customization Tool (OCT) Standard Settings |
| OP | ESignal OptionsPlus |
| OPS | Microsoft Office Profile Settings Format |
| OPTS | Linux Configuration Options Format |
| OPLC | Nokia Logo Format |
| OPN | Court Opinion |
| OPENBSD | OpenBSD Readme Format |
| OPTIONS | SE-SOFT Configuration Format |
