Error installation on Xperia 10 Android 2.3.3

[AndroidDevxp]

[FONT=&quot]Hi[/FONT]
[FONT=&quot]I am new to android. I have developed a little app on Android in 4.0 first and then I build it for Android 2.1.[/FONT]
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[FONT=&quot]I attempted to test my application on Xperia 10 Android 2.3.3.[/FONT]
[FONT=&quot]I wanted to release a version like it is sais there : [/FONT]
[FONT=&quot]developer.android.com/guide/publishing/app-signing.html#ExportWizard[/FONT]
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[FONT=&quot]I did what it is written on it from the section "Compile and sign with Eclipse ADT". Therefore I exported my project with the option "Export Android Application". It has generated a file apk.[/FONT]
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[FONT=&quot]Then I attempted to test my app on Xperia 10. In parameters/applications, I have allowed "unknown sources". I send the app by email and then I clicked on the email with the file apk. I clicked on it like I am told at this link :[/FONT]
[FONT=&quot]developer.android.com/guide/publishing/publishing_overview.html[/FONT]

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[FONT=&quot]Unfortunately I got an error on Xperia 10 when I attempted to install the app from the email.
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[FONT=&quot]I also built my app for Android 2.3.3 but the error is still the same.[/FONT]
[FONT=&quot]How can I fix this issue ?
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[FONT=&quot]Thanks[/FONT][FONT=&quot][/FONT]