Let me tell you one thing before we talk about how to open an archive OST file without MS Outlook; it is almost impossible for a user to open any orphan or archive or inaccessible OST file in MS Outlook directly. Exchange server, Office 365, Outlook.com or, IMAP accounts creates OST files; thus no one can import or open it within any MS Outlook account directly just like that.
Once you unlink the OST file with the associated accounts, it becomes an orphan or, inaccessible file. And if you try to open such files, you will end up getting various OST files errors. That explains whether you have MS Outlook in your machine or not; it does not matter. If you want to open an archive OST file, then you either have to opt for some paid tool or try doing it manually, which is impossible without MS Outlook.
How to Open Archive OST Files?
Here, if I consider the fact that you only want to open an archived OST file; then it shows that you only need to view its content and nothing else. For that, you only have to have an OST file viewer, which does the job for you. Because; any old OST file which does not have any restore point will not open with any inbuilt program in your machine. Not even in MS Outlook. For doing this, you either have access to the account that has created the file or, you have to find the right OST file viewer tool online.
Such applications let you open any type and size of OST file irrespective of how you have created the file. You can view the entire data present in that archive OST file. Also, if you have multiple OST files to open, the tool helps you to open them all in a go. Here the challenge comes when you want to use the data present in those OST files. For this, you need to convert the OST file into some more portable file format that does not require MS Outlook to open.
If you want to export all the contacts from the OST file; then you can save them into Excel or CSV file format. But if you want to export emails, then you can convert them into EML or MSG file format. The EML file format is independent. You can easily open them with Notepad. And if you use any emailing application like windows live mail or, thunderbird; then you can import EML to that account to use them more efficiently. For doing this, you should know how to convert the OST file data to use them in your work proactively.
How to Convert Archive OST Content
If you don’t have MS Outlook, and you still need to open as well as access the OST file content, then OST file conversion is required. But then you have to convert the OST content into a more versatile file format. Like; for saving OST files, contact saving them into MS Excel file format will work. And if you want to convert OST emails, the best option is to export OST emails into EML file format.
You can opt for OST to EML Converter to export all your OST files into EML file format to open them with the applications like Windows Live Mail, Thunderbird, Outlook Express, Windows Mail, Eudora, Sea monkey. The EML file format is also readable by various web browsers. So, you can open them in Chrome, Microsoft Edge, or Internet explorer too. You can edit the file extension from .eml to .mht and, you are good to go.