Hello Claire,
Thank you for contacting AVG support community.
We are sorry for the trouble caused.
Please confirm if it works on any other browser.
Please confirm on which browser your facing this issue?
We will certainly help you out.
Thank you and keep us updated.
I just updated my AVG browser version - seems to have done the trick 
I can no longer open my hotmail account on the Avg browser
I just updated my AVG browser version - seems to have done the trick
Thank you for writing us back, Claire.
May I know your AVG browser version?
Also could you please confirm if you are getting any error message while opening hotmail on AVG browser? If yes, kindly share us a screenshot of the same by referring the below article.
https://support.avg.com/SupportArticleView?urlname=avg-create-screenshot
You can post the screenshot here in your topic. Click on Answer & then click on the Image [mountain symbol] & follow the instructions.
Thank you and keep us updated.
Hello Claire,
Thank you for contacting AVG support community.
We are sorry for the trouble caused.
Please confirm if it works on any other browser.
Please confirm on which browser your facing this issue?
We will certainly help you out.
Thank you and keep us updated.