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"No registered application for this extension" Opera 12: How to fix?

  • When I go to any URL I get this popup.
    "No registered application for this extension"
    What caused this? It was working fine the last time I used it.

  • You've told Opera to use some other program to open web pages.

    Go to Preferences > Advanced > Downloads and search for "html". If you find text/html, select it and click on Edit and make sure it is set as "Open in Opera". If there are other listings for html, might as well check them too, but text/html is the main one.

  • I do hope you all realize this is about Opera 12.8, not the Chrome Opera.
    @sgunhouse When I go to Preferences > Advanced > Downloads I have a box with 2 columns: MIME type & File Extension(s)
    Neither has text/html.
    What I don't understand is why wouldn't Opera just open a HTML document if one is using Control_O to open it? You're in the program. What else would it possibly use to open it? You've told it to open a program. Its like using VLC to open a mp3 file by opening VLC first then using Control_O to open that file. I've never had this happen before.

    Anyway I thought I'd better just re-install it. It was working fine yesterday but now I can't go to any URL. Something must have gotten corrupted.
    Sorry for not being more clear in my original post.

    I can open HTML documents though. Just no URL's entered on the Address Bar or if I click on a bookmark.

    I should mention my default browser (Firefox) is working fine.

  • In that case, clear the checkbox that says "Hide file types opened with Opera" and check again, though if you didn't see it the first time that should mean it was set correctly ... there are 7 file types listed in my copy when I clear that option before searching (including text/html). All of them should be set to "Open with Opera" when you try to edit them.

  • @sgunhouse Yeah, that was it. Didn't see it. When I search for htm or html I get 7. As they just appeared I thought it odd they wouldn't be opened by Opera as we just cleared the option to hide those that are opened by Opera. Anyways they are all set to open by Opera.

    Any suggestions?

  • @sgunhouse I should have mentioned what it does say in the File extensions column.