[Sony Xperia P, U, Sola, Go] The_0bserver:
For those that are unable to get their drivers installed properly, there is another way that this can be fixed. (Without the use of Flashtool since that doesn't seem to be working for u guys, It should, but can't guarantee since I'm not a Go user.)

Once you connect your phone via USB. (make sure that the cable is working - connect your phone while it is off, if phone starts, then cable msot prolly is fine). Then go to device manager in Windows (I assume u guys are on windows,since Linux wouldn't have driver issues). For Windows 7 or 8 just type Windows onto start search. For XP - right click on My Computer -> Device Manager. (If that ain't working for you, just google it to see the steps clearly).

Once you are inside Device Manager, First off make sure that the device is connected properly. If your phone is having bootloop issue (where your phone keeps restarting again and again), connect the phone in Flashmode. (Google how to get into Flash mode for your device - It basically involves starting the phone[that is phone should be off before trying] and then pressing a certain button or a combination of buttons while connecting the usb cable to your PC/laptop)

Now In device manager you should either see Unknown device OR Android mobile phone (or something similar).

For unknown Device, Double click on the Unknown Device option and from the options given Right Click ->Install/ update Driver Software.

If in case you did mess up while trying to do this - example remove the cable before the installation completed, then uninstall then click on install again.

If successful you should an option similar to Android mobile Device. (sometimes you are already at this step, wihtout having to do the previous stuff), then Double click Android mobile device, and right click on the new options. (For me at one point it was 3, later on it was 2, yours can be more or less). If you understand what they do, then select the ones that you need, else you could just go ahead and install all the drivers from those options.

This should work out perfectly for u.I did this while I was having Bootloop issues, and had some ROM problems. Did this to get adb shell working so that I could push a file into the SD card from which i could install. This method should work unless U've completely bricked your device. You could probably use this even in case of soft brick .

Use titanium backup (Download either the free version/pro version from Play Store) if you have root (that is the best available option.) Else there is a backup tool that is currently on the news feed on the Front Page of xda (should be around bottom i guess), . Both these options should be better than Backup and Restore.

Why did you format your sdcard/external sd card? When resetting data, that does not wipe sdcard, so formatting the sd card just made things bad.

Still not to worry,it is fixable.

First off which is your phone? And what ROM are you using? Stock - that is the ROM that came with the phone??

now onto the main part -

Connect your phone in Flash mode (Google how to get into that mode for your device). And flash a Stock ROM.

if somehow that is not possible for you and you can do it only through CWM, then you wil need to copy the ROM onto your sdcard.

If you can remove your sd card, then do remove the sd card and connect it to a sd card reader (you might have one already in a laptop etc), and just copy paste a stock based ROM onto it, and then flash that by using something like Flashtool.

If your sdcard is NOT removable, the you will have to use something called adb to push the files to the sdcard. you will have to download the android sdk, install additional drivers. (you may have to follow my instructions for installing the drivers, as I said at the top of this post to install the adb drivers). Once you've set up adb, just push those files into your sdcard, and then go from there. NOTE that with sdcard (with or without adb)-> CWM method, you most probably will not be able to flash stock ROM as that involves something called an ftf file (which includes a.sin file) which does not work with CWM. In this case use the other custom ROMs built for your phones. Since in abhilv01's case i believe his phone does not have an unlocked bootloader. hence make sure to choose a ROM that DOES NOT require unlocked bootloader.

Also note that flashing a stock ROM might probably result in you loosing root, and you will need to re-root it again to gain root privilages. Just search the stock ROM thread to see if some special method should be used to root that stock ROM.