It is a typical situation. You installed Ubuntu or Windows XP over Windows 7, and now you can boot only the last installed OS. You wish to get back the multi boot menu that lets you boot all OSes
The first step is to restore the Windows 7 bootloader
Boot off the Windows 7 installation disc, click through all options till you get an option “Repair your computer” in bottom left. Choose the correct Windows 7 partition and click Next.
Now you get the System recovery Command Prompt
To restore the Master Boot Record with Windows 7 entry:
bootrec /fixmbr
If this fails to fix your issue, you can write a new boot sector to System partition with:
bootrec /fixboot
All the options supported by bootrec can be viewed with:
bootrec /?
Recover Windows 7 Bootloader after installing Windows XP on top of Windows 7:
bootrec /nt60 all
Joel G Mathew, known in tech circles by the pseudonym Droidzone, is an opensource and programming enthusiast.
He is a full stack developer, whose favorite languages are currently Python and Vue.js. He is also fluent in Javascript, Flutter/Dart, Perl, PHP, SQL, C and bash shell scripting. He loves Linux, and can often be found tinkering with linux kernel code, and source code for GNU applications. He used to be an active developer on XDA forums, and his tinkered ROMS used to be very popular in the early 2000s.
His favorite pastime is grappling with GNU compilers, discovering newer Linux secrets, writing scripts, hacking roms, and programs (nothing illegal), reading, blogging. and testing out the latest gadgets.
When away from the tech world, Dr Joel G. Mathew is a practising ENT Surgeon, busy with surgeries and clinical practise.