You can update your email address at https://www.isc2.org/MemberHome. Your username/password should be the same as you use to login to the community because (ISC)² federates logins between their websites.
How are you logging into community.isc2.org and posting then? When I click the community "login" button, it redirects me to www.isc2.org, which is the exact same login page that memberhome uses.
Member support can also look up accounts with your (ISC)² member number. If you can not remember that either, it can be found on the PearsonVUE "My Profile" page. It is also on the PearsonVUE exam confirmation email and your receipt for payment for the exam.
As you work through this, you might think about how you would convince member support that you are not a bad actor attempting social engineering techniques to gain access to somebody else's account. One effective way of doing so is emailing (ISC)² a copy of your PearsonVUE receipt and requesting they update their records to match the address found on the PearsonVUE receipt.
I have created a new account with new email address to login to (ISC)2.
Yes, I can login to Pearson Vue, and see my results. I also have the payment receipt with me on email my id.
All these recent transactions, and exam results are available with my new email address/account.
But, when I initially registered myself with (ISC)2 i.e. 4-5 yrs back, I used a different email id which I can no longer access.
So, I assume, (ISC)2 is still sending all the communications to my old email account as someone from the support team from (ISC)2 has already confirmed that they are unable to locate my account with this new email id.
I just want (ISC)2 to send me the email notification & endorsement process links to the new email account.
I can also help the team with my ID/Examination number if required. They must also be having other details of mine which definitely can prove my identity.
@billclancy is right. Call member services. If the number he provided does not work from your location, other options are available at https://www.isc2.org/Contact-Us. Also, their hours are something like 8-5 M-F US eastern time. Don't be surprised if they don't respond outside of their work day.
They will need the member number for your new account (found at https://www.isc2.org/MemberHome) and also the member number you provided to PearsonVue when you took the test. I suggest you have those ready when you call.