As it is known that iPhone messages can either be backed up to your computer through iTunes or to iCloud if you have enabled the related iTunes or iCloud backup settings, which makes sure that you can restore your iPhone to get backed lost or deleted text messages.
The drawback is that you cannot extract the iPhone text messages from the backup. In other words, you cannot view the text messages even if you can precisely locate where the backup file is. If you back up locally on an Apple machine, you can find the file under Library > Application Support > MobileSync > Backup. If you back up to a Windows Machine, you can find that file in C:\Users\[USERNAME]\AppData\Roaming. And the messages stored in the backup file will be lost forever once the backup file is corrupted accidentally.
There’s an online service where you can upload that file and download the content and metadata in either PDF or CSV form. Of course, it’s totally up to you whether you want to give some old website access to your private messages.
There is also a desktop application can solve all your problems. iFonebox, as a specialized iPhone data recovery software, can download the text messages from your iPhone selectively. Here is how.
> Install and run iFonebox on your computer.
> Note: iFonebox is available for both Windows and Mac OS users, please choose the right version to download and install.
> Connect your iPhone to your computer.
> Click “Start” after your iPhone is recognized by iFonebox.
Tips: If your iPhone cannot be recognized by iFonebox, please check whether you have trust the computer when it is connected to computer.
> Choose messages to download selectively by clicking the related icon from the interface listing all the supported data categories.
> Wait until the data scanning and analyzing completes.
> Preview the exported messages and select whatever you need to download to your computer.