Also Read: Guide to Migrate Old Emails to Office 365 Step by Step
IONOS and Office 365 Differences Explained
Use this tabular comparison chart to identify the exact reasons why many of your peers choose M365 over IONOS and what you should, too.| Feature | IONOS (Mail Business) | Microsoft 365 (Business) |
| Primary Focus | Web/Email Hosting | Enterprise Productivity |
| App Suite | Webmail only | Full Office Suite (Word, Excel, etc.) |
| Collaboration | Basic Email | Teams, SharePoint, OneDrive |
| Email Storage | 50 GB Hard Cap | 50 GB / 100 GB + Archives |
| File Storage | None (Add-on required) | 1 TB OneDrive per user |
| Security | Standard Spam/AV | DLP, ATP, and Entra ID |
| Integration | Limited / Manual | Native Ecosystem & Power Automate |
Prepare to Migrate IONOS to Office 365 Successfully
The best way to reduce migration-related troubleshooting tickets is to prepare thoroughly. The following tasks do exactly that.- IMAP throttling: For a large IONOS server ( > 10 GB), you have to request a temporary “EWS Throttling”. Contact the Microsoft support staff directly. There are no such settings in the admin portal. Moreover, without throttling enabled, your M365 ingestion speed slows down to a crawl, and it takes forever for the migration to complete.
- Make a New Subdomain: As per the official guidelines, any shift out of IONOS needs a temporary subdomain. This is done to prevent the vicious cycle of “Domain already in use.”
- Have Licensed User Accounts in O365: You can’t put data in if there is no recipient. So make sure you study the various Office 365 plans and choose the one that works best for your organization. Then add the user accounts there.
Migrating Emails from IONOS to Office 365 on Your Own
This Do-It-Yourself approach is split into two parts. Part 1 is configuring the M365 endpoint:- In the Exchange Admin Center, look for Recipients > Migration > Migration Endpoints.
- Then, add a new IMAP endpoint with server URL as imap.ionos.com.
- Click the “+” (plus) icon > Migrate to Exchange Online.
- Then, choose the IMAP migration option from the list.
- Add your CSV mapping containing user data.
- Tap on New, which will start the background sync.
Problems with the DIY Approach
The most common complaint by IT admins is that the Exchange Admin Center, the site used to carry out the transfer, is too confusing to navigate. Not only that, but numerous options that have nothing to do with each other are put together. Moreover, the dashboard is static. Suppose you access one set of services often, and it is buried deep in 3 layers of menus, you can’t pin it for easy access. All of this makes it quite confusing to carry out the migration from IONOS to Office 365. If menu mayhem wasn’t enough, the process itself has large security gaps. For instance, the CSV sheet needs user passwords in plain text format. This alone makes manual transfer a highly risky operation. If by chance the CSV leaks, the entire organization’s data could be in jeopardy. The built-in option won’t be able to detect newly arrived emails. So you have to transfer them manually or leave them behind; neither option is ideal. To bypass all these issues, I have an excellent professional method, so check it out.Automated Alternative for an Error-Free IONOS to O365 Transfer
SysTools IMAP to Office 365 Migration tool is an all-in-one solution for this purpose. Built to shift a massive amount of email data with speed and safety. Choose it for a script-free, pure GUI experience. With options to filter dates, users, and apply prioritization to VIP accounts, the tool has it all. Moreover, you can evaluate the migration results with reports and perform multiple reruns to capture newly arrived or missing data, too. Nothing else can make your IONOS to M365 shift as easy as this tool does. Start with a free demo today on Windows 10/11 desktop, also available for Windows Server 2016 or later. Unlike the O365 admin portal procedure, the steps to use this software are super simple. Step 1. Install your copy on a suitable machine, open it, pick Source as IMAP, and Destination as Office 365. Then, select Email workload and Apply the Date Filter (optional). Step 2. From the source screen dropdown, select the Others option and fill in your IONOS server details, validate them, and press Next to proceed. Step 3. Then, in the destination screen, add your Office 365 account details like the Admin email and Application ID. Validate both at the same time and hit Next. Step 4. In the user mapping screen, get the CSV template, and fill in the account details. Reupload the sheet into the tool. Step 5. Finally, select the accounts, apply priority marking, validate, and start.What to Do After Migrating IONOS to Office 365
The task does not end with the data shift. Admins must ensure that new accounts are working properly. For that, they need to do the following: Updating DNS records is non-negotiable. Without them, you won’t be able to receive any email, as other recipients would still believe that you are at the old address. So, log in to your Domain Registrar and update the MX record to point to yourdomain-com.mail.protection.outlook.com. Likewise, don’t forget to set up SPF, DKIM, and DMARC in Office 365, which are responsible for outgoing email.Also Read: Migrate Cogeco Email to Microsoft 365 Step by Step
Decommission old IONOS. Just like what my suggestion was in the guide for migrating IONOS email to Gmail, here too, after an extended cooldown period, you must close old accounts manually. If you stop paying, IONOS will eventually close the account.Conclusion
Here, I taught users how to migrate IONOS to Office 365 in two different ways. The manual process is not that difficult. However, it is the manual method’s unintuitiveness that makes admins prefer the automatic solution. The tool handles all the heavy work while you focus on more nuanced subjects like preparing users for the new environment.Frequently Asked Questions
Open Recipients, Migration and Migration Endpoints in Exchange Admin Center and add a new IMAP endpoint with the IONOS server URL imap.ionos.com. Click the plus icon, select Migrate to Exchange Online and choose IMAP migration. Add the CSV mapping and click New to start the sync.
Exchange Admin Center is confusing to navigate. The CSV sheet needs user passwords in plain text, which is a security risk. The built in option cannot detect newly arrived emails.
Ask Microsoft support for temporary EWS throttling when the IONOS server is larger than 10 GB. Create a temporary subdomain and add licensed user accounts in Office 365.
SysTools IMAP to Office 365 Migration tool needs no script. Select IMAP as the source and Office 365 as the destination, choose the Email workload and add a date filter if you want. Enter the IONOS server details and the Office 365 admin details, upload the filled CSV mapping and start. Reruns capture newly arrived or missing data.