ICS duplicating in Outlook

Question

Hello, After the 1/9/24 security update any .ics files sent to a user to accept, etc. is duplicated when it is accepted. If you modify the appoint created by the ics file it is duplicated. This started last week with users after the security update was pushed out. Thank you

Answer 1

Hi @David Coull ,

I’m sorry to hear that you’re experiencing issues with .ics files being duplicated after the 1/9/24 security update. I found some information about the January 9, 2024 Security update (KB5034129) and January 9, 2024—KB5034123 (OS Builds 22621.3007 and 22631.3007), but none of these updates seem to address or mention any issues related to .ics files.

In this case, you could try the following general troubleshooting steps:

1. Check for updates: Ensure that your Outlook and systems are up-to-date. There might be a patch or update that resolves this issue.
2. Restart your system: Sometimes, a simple system restart can resolve unexpected issues.

If the issue continues, please provide more details for us to analyze:

1. May I know the account type are you using? Is it POP, IMAP or Exchange account?
2. May I know if you are using New Outlook or classic Outlook? Would you mind to kindly provide the screenshot of the outlook version are you using? (File > Office Account > About Outlook)
3. Have you tried any troubleshooting?

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