The top 10 things that can go wrong when migrating email from Google to Microsoft 365

You may have read our previous blog covering some recent migrations from Google to Microsoft that FortiTech has undertaken for clients, whilst those migrations went smoothly (phew!), it is not always the case and this blog covers off some of the pitfalls that you could experience migrating between the 2 platforms.  

Believe us, there was a reason that one of our clients decided against undertaking the migration themselves and engaged us instead.

Why make the move? 

There are many reasons you might choose to migrate from Google to Microsoft, they could be driven by cost, functionality or a platform preference for instance.

In the case of one of our recent clients it was the ease of functionality of the Microsoft platform for calendar sharing and linking with third party platforms such as HubSpot.

Once you have decided to make the move, there are some key areas to watch out for, which we will cover below.

The nitty gritty

Without further ado, here are our top 10 things that can go wrong when migrating from Google to Microsoft 365 (in no particular order)

DNS Access

Do you know what a DNS is, let alone have access to your DNS?  Changing your DNS settings is critical to setting up your new Microsoft mail tenancy and without access to your DNS is impossible to do.

Time to migrate

The decision to migrate from one platform to another should not be taken lightly or quickly for that matter.

The time to migrate 17 mailboxes for instance took 9 days, why 9 days you ask? Well, we will cover that in our next 2 points....

Google throttling data transfer

Google throttles the transfer of data from its servers, the limit is 2.5GB per day per user to be exact, leading to painfully long transfer times of mailboxes.  One of our mailboxes here at FortiTech is  22GB, meaning it would take almost 10 days to transfer that data (assuming no errors during the migration of course) if we were on the Google platform.

Microsoft throttling data transfer

Google isn't the only one limiting the transfer of data. Microsoft limits the migration of mailbox items to 1,800 emails per user per hour. So 100,000 small emails will take longer to transfer than 10,000 large emails with attachments for instance. 

Size of mailbox

The size of a mailbox not only impacts the time to transfer from Google to Microsoft, but if you don't have the correct licensing in place at Microsoft's end for the mailbox size, it will also fail to migrate.

As luck would have it, this error will only occur at the tail-end of the migration, so be sure to check the mailbox size first and license appropriately.

Shared mailboxes

For migration purposes a shared mailbox will need a Microsoft license to successfully complete, once in your new Microsoft tenancy the mailbox can be converted back to a shared mailbox and the license can be removed.

Time to download

Awesome! You have successfully migrated the mailbox across.  Now is the time to download the mail into Microsoft Outlook, again, this won't be instant and depending on the speed of your internet connection this could also take a day or more to complete.

Setting up groups

Mailbox permissions and groups you had set up in Google won't automatically come across to your new Microsoft tenancy, these will need to be set up again.

Relying on migration software

There are a lot of software tools in the marketplace offering to undertake the migration seamlessly. From our research most automatic migration software won't actually copy across items such as tasks and notes and instead just focus on the mail.  


What if you don't actually have administrative access to your Google Workspaces tenancy? Perhaps you had a previous provider that set your business email up, they were the administrator and you have since had a falling out.

It happens more than you think, we have experienced this with not only Google Workspaces but websites and servers where a client has terminated the services of a previous technology provider and have no administrative access to their data.

If you are keen on avoiding a few more grey hairs why not check out our Gmail to Microsoft 365 migration offering below.

What's on offer and what does it cost?

FortiTech offers migrations from Gmail to Microsoft (Office) 365 with added Backup365 and email antispam, these have been the most popular product option to date.

Backup365 provides a backup of email and SharePoint file storage and our email antispam product features anti-malware and antivirus protection that utilises 5 scanners for enhanced protection.

Here is a run down of our current offerings with pricing:

Microsoft 365 Security

With phishing attacks the number one attack vector, we ensure your organisations email is secure with 5 Anti-virus & Anti-spam engines, full message queuing, Outbound Filter, & Message Continuity/DR webmail.

 $9 per licensed mailbox in Microsoft 365 

Microsoft 365 Backup

12 months backup of all email, OneDrive and SharePoint is available as a separate option without our antispam and phishing protection

 $7.50 per licensed mailbox in Microsoft 365 

Microsoft 365 Security and Backup

We can offer a Bundle deal for our mailbox security with up to 30 years backup for Microsoft 365

$15 per licensed mailbox in Microsoft 365 

* requires Microsoft 365 to be billed by FortiTech and a continuous subscription to ensure backups               

Installation of Microsoft 365 Security and Backup products (once-off)

$25 per mailbox 

Mail Migration

We will manage the migration of all existing tasks, calendars, contacts, folders and mail from your existing platform into Microsoft 365. Includes setup of Microsoft 365 suite and email accounts on Outlook.

Does not include SharePoint file migration or setup.

$500 base fee PLUS

$150 per mailbox 

All prices quoted above are correct at the time of publication and are GST exclusive.

If you are ready to discuss moving your business from Google to Microsoft just give us a call on 1300 778 078 and we will get you on your way to a more productive workplace.