Sony Ericsson Xperia X10 — Unable to find

Now ive tried looking around for the answer but i havent been able to find it.
Settings/Applications and check "unknown sources"
Ive gone through everything in my settings more then once but cant find where it says unknown source.
Ive looked through my applications but the only options it gives me is to manage the applications or development
if anyone is able to help me out that would be really great cause i would really like to download AndroidPIT App Center
I have a att phone and im in the usa, Ca
I have the sony ericsson Xperia 10a

From what I have read, ATT has disable unknown sources. Normally the Xperia 10a should have the option under applications, but ATT has taken it out.

Jeremiah is correct. You can still download the AndroidPIT app from the Android Market, but the AndroidPIT App Center is not going to be installed on your phone until AT&T changes their policy (or maybe you root your phone, but that is a topic for much later).

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Awww man that stinks.....well i guess i have to go the other rout lol XD
thanks for letting me know that it wasnt me and bad searching skill
XD

If your considering rooting, take a look at Douglas' post on what it's all about: http://www.androidpit.com/en/android/forum/thread/403299/So-what-exactly-is-rooting-and-is-it-for-me#p509213

Ok well be for I go off and mess around with that I remember that where I download the app it said something about an apk or something like that. Is there an explination on that somewhere and also would it work on my phone or would it still be blocked out?

.apk files are a type of file, just like mp3, avi, or jpg. Your phone cannot run .apk files from unknown sources because AT&T blocks that. .apk files are the file type that apps are installed from.

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i see : )
well thank y'all kindly for helping me out
= ^ . ^ =