Yeah, this forum is a little "Advanced' but if you look around a bit there is pretty much all the information you need to figure things out.
>i too am having the problem with the pakage file invalid error on EVERY app i try to update or add... & its driving me nuts
It is frustrating. Hopefully we can help you out.
When people refer to a "ROM" what they mean is the software that is embedded in the device. When you first bought your phone, it came with either Android 2.2 Froyo or 2.3 Gingerbread as the operating system. This is what is known as the 'Stock ROM' because it is what comes 'stock' with the phone. You can find out which version you have by going to your phone's home screen and hitting the Menu key and selecting System Settings (or something similar), it should take you to a menu, the bottom option of which is "About Phone". There is a bunch of useful information in there, look under Android Version it will likely say 2.3.something. This means you are using the "Stock Gingerbread ROM".
Don't worry about what the Dalvik Cache or Link2SD are, just yet. That is stuff related to custom ROMs and/or requires you to gain 'root access' to your device. Basically it means we have voided our warranties so that we can do things the "Stock ROM" doesn't support. It's a lot of fun but not for everyone, it is not something most people need to worry about.
First of all, this probably isn't the case for you, but let's make sure you don't have 'debug mode' turned on, I was getting a package error file from the play store because I forgot to turn it off.
Go into the system settings menu, and choose Applications, then Development. Make sure the "Android debugging" check box is unchecked.
Once that is done hit the back key once to get back to the Application Settings menu. Then choose "Manage Applications".
It should take you to a list of the apps on your device. Choose "All" from the tab at the top, and scroll down until you see the Google Play Store app.
Click on that and chooose, "Clear data", and "Clear Cache" As soon as you do that, power down your phone and reboot it. Once it is back up, go to the Play store, (you may have to sign into your google account again) and try install the software that was giving you the errors before.
Hopefully that will solve your problem, let me know if it worked
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