Outlook 2025 - When i import meeting to a room mailbox calendar from old room to new room calendar it show in my outlook desktop application, but it doesn't reflect in Outlook Web Application or my other outlook desktop application. Which I want.

Question

When I imported meetings from CSV file to a room calendar, it started to show in my outlook desktop application. But when I look up for those same meeting using outlook web application(OWA) or another account that has access to view meetings scheduled in that room. I am unable to see those email. When I removed and readded those room in my outlook. Those meetings were no longer there. I came to a conclusion that the calendar is saving localy on my desktop therefore is showing me the meeting but is not updating globally. However I want it to be such that anyone who opens free busy or views calendar in any viewing allowed access right category. Those Imported meeting should be visible. Any solution that can be taken?

*Note - I am not sure if I am using outlook classic or New.

Answer 1

Hello Singh Yuvraj - Munich-MR - external,

Thank you for posting your question to Microsoft Q&A forum.

Since you are using the File > Import/Export feature to import a .csv file, you are using the Classic Outlook.

When you have a Room Mailbox added as a "shared calendar" in Outlook, your computer keeps a local copy of it in a cache file (the .ost). When you import a CSV, Outlook dumps the data into this local cache but then does not synchronize (upload) those new items to the server. This is why the items are only visible to you.

To bypass this, the best recommended workaround is to import the file using Outlook on the Web (OWA). This is the cleanest solution as it bypasses your desktop app entirely and performs the import directly on the cloud server.

Here are the steps:

1. Close your Classic Outlook desktop app.
2. Open a web browser and go to outlook.office.com
3. Go to your Calendar.
4. On the left-hand menu, click "Add calendar".
5. In the window that appears, look on the left for "Upload from file".
6. Click "Browse," select your .csv file.
7. This is the most important step: You will see a dropdown menu titled "Select a calendar". Do NOT choose your personal calendar. Find and select the Room Mailbox calendar from this list.
8. Click "Import".

This will upload the .csv file directly to the server and populate the real Room Mailbox calendar. It might take a few minutes, but after this, the meetings will be visible to everyone, on OWA, and on their desktop apps.

I hope these steps help you get the calendar populated correctly. Please let us know if this works for you.

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