Opening Gmail Attachment With App

I need to open files with custom extension using my app. I am able to do this using Intent filters when the file is in my sd card. I can also view the 'download' and 'preview' buttons if the file is sent as a Gmail attachment. However, when I clicked the download/preview buttons, I got the message - "Sorry, the attachment could not be downloaded".

I thought this was an issue with my app. But I had a random idea and installed "Download All Files" app on my phone.URL....Then, when I click download button in Gmail, both Download All Files and My App are proposed for downloading the file. I chose my app, and everything works fine!!

[HIGH] <intent-filter >
<action android:name="android.intent.action.VIEW" />
<category android:name="android.intent.category.DEFAULT" />
<category android:name="android.intent.category.BROWSABLE" />
<data android:mimeType="*/*" />
<data android:scheme="content" android:host="*"
[code]...