update: restarting my Macbook made me able to launch Electrum and open my wallet again.
Maybe electrum just crashed. Thanks.

Hello,

I am puzzled by what happened to my wallet:
I bought a Trezor, installed and connected it to my PC.
Next I did a test transaction from my Electrum wallet on my Macbook to the trezor wallet connected to my PC.
I received the bitcoin amount.
Next I wanted to open my wallet again on my Macbook and get this message: ''you are opening the application Electrum for the first time. Are you sure you want to open this application?

What happened to Electrum & my wallet?
Thanks.

Thank you for your help!

@HCP: I will install a new version of electrum on my new Macbook and follow your steps.

@coin-keeper: Thanks for the warning. I was planning to move my coins to an online wallet like blockchain, but will investigate hardware wallets.

Hello,
I searched for a guide online to change my watching only wallet into a normal wallet to be able to use my bitcoins but could't find any, therefore I hope someone here can help me.

Situation:
- Several years ago I installed Electrum (version 1.9.5) and bought bitcoins.
- Next I changed the electrum wallet into watching only and never looked back, the same version of electrum is still on my PC.
- I did write down a phrase of 12 words that I still have.

Now I want to spend the bitcoins, but I unfortunately forgot all about how electrum works.

Can someone please help me with the best steps to take to change my wallet back to normal?
I can use the same PC (W7) or my newer notebook, whatever is recommended.

Thank you.