You need to stop anything happening on your computer before taking any more steps. Period. I would not trust your computer to anyone that you didn't trust with your life.
You said that the operating system of your old PC (Windows 7) was dead. This can mean so many things and is very vague.
In order to help you we will need a lot more information. Is it a laptop or desktop? Can you get into the BIOS? How exactly is it not working?
These questions are important to determining a path forward. It's possible that you could take your old hard drive out, connect it to another Windows PC and it will be accessible there. As long as your hard drive is not physically damaged it should be an easy process to get the wallets out. There are adapters that will allow you to connect via USB. Even if your hard drive is complete toast and is not accessible in another machine there is some hope. If the value of your coins was worth it, you could send the hard drive off to a specialist to recover the data. This option is very expensive, but might be worth it if you have enough coins on your drive.
Give us more detail...
Thanks
It is an HP laptop.
I tried to access the Bios and disinfect the computer from the Kaspersky image without success.
I searched the hard drive which is in good condition from another PC without success either because I do not really know where to look.
I only found a file "investment.dat" (concerning my Litecoin) that I had saved but when I open them, they are incomprehensible encryptions. I also came across PGP keys.
I also found a QR code for my Dash, but it looks more like a receiving address.
I checked the addresses where I sent all this and the LTC and DASH are still there.
So I took my computer to a repair specialist and told him that I did not want to lose anything. He reminded me that I should reinstall all my software (as mentioned in the post)
At the time I invested about fifty euros..They are worth 10,000 today. So, yes, I absolutely must find a solution, no matter the price.
Thank you for your relevant answers
THIS IS USEFUL INFORMATION!!!!
Okay, on your OLD hard drive, Navigate to:
USERS > OLYMPIEN (or whatever your main account is).
At the top of the window, click VIEW. Look for the checkbox for HIDDEN ITEMS. Make sure it is checked. This will show all the hidden files. Your wallets are in a hidden folder.
When Hidden Items is checked, you should see a folder called APPDATA. Click this, then click ROAMING. All your wallets will be in Roaming.
In the roaming folder you will see various folders. Among them your various coins. Click the Litecoin folder. Inside you will see a file called WALLET.DAT. Save this file to a thumbdrive.
Most coins all use the same wallet name, they are all called wallet.dat (there are some that don't). If you see a wallet.dat, copy it to its own separate folder. We will get back to that in a minute.
Once all your wallets are secured, you can go about recovering your coins.
I do not know if wallet.dat files are compatible with OSX. You may have to do the recovery process on Windows.
To recover your coins on Windows, before doing anything with the rcovered wallet.dat files, download all your various coin wallets, run them, and let them sync. Once synced, you are going shut them down.
USERS > OLYMPIEN > APPDATA > ROAMING and open up each folder, one at a time. Rename the NEW wallets to something like walletBAK.dat or whatever, you won't be needing these again. Copy the OLD recovered wallet.dat file into the same folder and restart the wallet. Your coins should be visible once it re-syncs with the block chain.
A word about passwords. If you put passwords on any of your old wallets you will need to know them here to get any use out of them.
Ethereum does not use wallet.dat, they use a different method. I am not sure if DASH uses wallet.dat, but there will be a DASH folder in roaming. If unsure of what to copy, copy the entire folder to be safe.
