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Best cloud migration services: How to fight lock-in and switch providers

This article shows you our pick of services that can help you fight lock-in and switch to other providers. This may well be a must-read for any IT operation increasing its reliance on the cloud.
Written by David Gewirtz, Senior Contributing Editor
Google Workspace Migration for Microsoft Exchange (GWMME) | Move Exchange to Google
Google Workspace Migration for Microsoft Exchange (GWMME)
Move Exchange to Google
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Microsoft Exchange Admin Center (EAC) | Move Google to Exchange
Microsoft Exchange Admin Center (EAC)
Move Google to Exchange
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Best tool for migrating messaging systems | Transend
Best tool for migrating messaging systems
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Best tool for moving your help desk system | Help-Desk-Migration.com
Best tool for moving your help desk system
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Best tool for migrating to or from Salesforce | Trujay
Best tool for migrating to or from Salesforce
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Best tool for migrating cloud storage cloud-to-cloud | MultiCloud
Best tool for migrating cloud storage cloud-to-cloud
View now View at MultiCloud
Show more (1 item)

According to statistics aggregator service Statistica, organizations used an average of 80 cloud applications in 2020, up from 16 just three years before. With this level of investment and reliance on cloud-based services, both users and companies will inevitably want to move from cloud service to cloud service. 

I've written before about how cloud vendors can capriciously change their policies and pricing and how lock-in can arise out of cloud reliance. Once you're fully invested (and therefore fully reliant) on the cloud, this can be a real problem.

But just because the cloud can be a somewhat challenging place when it comes to lock-in and switching costs, that doesn't mean you have to be locked in. This article shows you our pick of services that can help you fight lock-in and switch to other providers.

Messaging migration the Google and Microsoft way

We're going to kick off our cloud migration "best-ofs" with the services that Google and Microsoft each offer to assimilate customers from their competitors. Google has a tool to pull in Microsoft users. Microsoft has a tool to pull in Google customers. Neither are super easy or super-convenient, but they're part of the overall platform offering. Right after, we'll show you a paid-for service that can do all the migration for you. But for now, let's look at native solutions.

  • Servers supported: Microsoft Exchange Server 2000, 2003, 2007, 2010, 2013, or 2016.
  • Cloud services supported: Exchange Online (Office 365).
  • IMAP support:  RFC 3501-compliant IMAP server (including Exchange, Novell GroupWise, Cyrus, Courier, Dovecot, SunMail, Zimbra, or Gmail).

GWMME supports migrating email, calendar, and contact data from Office 365, Microsoft Exchange, and some IMAP servers to Google Workspace. Interestingly, migration doesn't occur in the cloud. Instead, you need to set up a local Windows machine on-premises, which sucks Microsoft data down and then pushes it into Google Workspace.


  • Included in the cost of your Workspace plan
  • Has some support from Google
  • Moderately configurable


  • Must run on a local client machine
  • Moderately complex to setup
  • Limited support from Google
  • Workspace migration: Mail, contacts, calendar
  • Scripting: PowerShell supported

Microsoft has its own migration tools. You can choose to use the Exchange Admin Center or set up your own scripts using PowerShell. Both will require some customization and tweaking.

There are also some substantial migration limitations. Shared calendars, cloud attachments, and event colors will not be migrated. Microsoft also says that "A maximum of three email addresses per contact are migrated over, and Gmail tags, contact URLs, and custom tags will not be migrated from Google Contacts." Additionally, attachments are limited to 35MB, although that can be adjusted to 150MB if a setting is tweaked.


  • A number of different approaches are offered
  • Multiple runs are possible


  • Migration not available for Office 365 US Government GCC High or DoD
  • Attachments limited to 150MB (after setting tweak)
  • Migration tool doesn't work with records management (MRM) or archival policies

Services that can help with migration

In this section, we will spotlight services that can help you migrate or perform migrations for you. Generally, these services charge per user being migrated, the amount of data being moved, or both. But because you're paying for a specific migration service, and that's what these vendors do, you have a far better chance of getting more hand-holding and support than the solutions shown above.

  • Microsoft: Microsoft 365, Exchange/Outlook, PST, OST, Outlook MSG
  • Google: G Suite/Gmail legacy, Google Workspace
  • HCL/IBM: Notes Domino, NSF, SmartCloud
  • Micro Focus: GroupWise
  • AWS: Amazon WorkMail
  • IMAP, etc: Communigate, EML, Eudora, First Class, GoDaddy, Kerio, Mdaemon, Mirapoint, MBOX, Netmail XML Archive, Oracle Communication Server, Pegasus, POP Server, Rackspace, Sun/Oracle JES/iPlanet/One, Thunderbird/Netscape, Yahoo, Zimbra, generic IMAP

If you have messages you want to be moved, this service can do it for you. I've known the folks at Transend for more than a decade, and they've been offering migration services for at least that long. Back when I was the editor of DominoPower Magazine (before I was at ZDNet), Transend used to help Domino users move to Exchange.

Today, they move from and to a very wide range of services, shown above. The basic plans support email, calendars, contacts, tasks, archives, while their enterprise plans and professional services can also convert rooms, resources, groups, distribution lists, delegation, aliases, other active directory attributes.


  • Very wide range of conversion sources and targets
  • Lots of experience


  • Some advanced conversions require enterprise or professional services plans
  • The lowest cost plan requires end-user authentication per mailbox
  • Platforms supported: More than 170
  • Pricing: Based on #records being moved

It's odd when a company that sells tech support software has terrible tech support. But that was the case with Awesome Support, which had an awesome tech support plugin for WordPress, and non-existent support. After a few years running this product -- and building a considerable database of users and their problem tickets, I decided it was time to switch. I chose Help Scout, but the real challenge was I didn't want to lose all that help desk history.

Because Awesome Support was relatively small compared to the mainstream cloud help desk companies, I didn't expect to be able to migrate all my tickets. Then I found help-desk-migration. Not only did they do the migration, but they were helpful along the way.


  • I had a very successful migration
  • A ton of platforms supported
  • Good, highly responsive support


  • Wish they supported other types of SaaS software beyond help desk
  • Supported CRM platforms: 180+
  • # free test records: 10

Trujay supports an absolutely mind-boggling number of CRM systems. CRM data is notoriously difficult to migrate because every vendor implements relationships between companies and individuals and their roles in the companies differently. But Trujay has a migration wizard that allows you to choose your source and destination CRM and then run the migration. Trujay will run a sample import without requiring payment, so you can test how you like the service.


  • A huge number of CRM platforms supported
  • Offers additional backup and export services


  • No pricing published on the website
  • Test size is only 10 items
  • Services supported: 30+
  • Data caching: no files or data is cached

Cloud file storage can be a very useful tool for both individuals and businesses. Not only does it provide file access from anywhere, but it also serves as a great off-site backup mechanism. But what happens when you decide to change services because you've hit a storage cap or the prices at your current vendor have skyrocketed, or something continually breaks down?

Do you download everything and then upload it again? If you have a few gigabytes of storage, it's no big thing. But it can become problematic when you start to push into the terabyte range (I have something like 27TB in cloud storage). Downloads might not be bad, but uploads could take forever.

A better solution is doing a cloud-to-cloud migration, where your data never has to return on-premises. MultiCloud offers such a service, allowing you to move files from a wide range of cloud storage providers to other cloud storage providers. Pricing is based on how much data you use per month, but the $120/year plan allows for an unlimited number of services and an unlimited amount of data. Of course, unlimited is never truly unlimited, so check their terms of service for any gotchas.


  • The $120/mo unlimited plan is aggressive and powerful
  • Service supports scheduling and filtering
  • Supports non-public cloud through FTP


  • It would be nice if public cloud vendors including some of these features
  • Users report some transfers get "stuck"
  • No mobile app


What about security? Can I trust these companies with my data?

That's a very good question. Let's be clear: we did not do a security audit for any of these companies. Some companies are in different countries, and those nations may have different data integrity regulations. If you're concerned about security, start a dialog with the vendors, but also look at discussion boards and forums for any user reports. Ask for independent audits, if available. Do your diligence until you feel reasonably secure. But do not forget: your data will traverse the servers of these companies, which means it may well be at some risk. On the other hand, how much due diligence did you do before putting your data in the cloud in the first place?

How fast are the transfers?

There's no set answer to that. It depends on what clouds you're using and moving to, as well as how much data you need to move. I've done a few email migrations for my small company and one big help desk migration. It all took about a week. Most of the time was spent communicating back and forth with the migration vendor and getting the transfer just right. The data movement itself was relatively quick. But moving that 27TB I currently have in cloud file storage would definitely take quite a long while, no matter what service is used.

What if I have special needs?

Again, that will depend on what the needs are and the vendor. I had some very special field migration requirements moving off my help desk to the new vendor, and I discussed that with Help-Desk-Migration.com. Some of the tweaks I asked for were easy for them to implement, while others were just too ambitious. It's all about good communication between you and the migration vendors, being clear in your communication, and doing enough pre-planning that you're able to use whatever help they can provide.

What was your methodology in selection?

As is often the case with these lists, I use a combination of personal experience and peer input. I've gone down this road before, so I try to share my personal experience making it happen. I also reach out to IT managers and professionals for their recommendations and input. For this list, I tried to find vendors who had a large range of conversion options. 

My reasoning is that a company that can convert from a lot of CRMs to a lot of CRMs will understand the generalized data structure for a CRM. Likewise, for help desks. This means that as they move data, they have to build mechanisms for application migration with context, not just a set of field transfers. Also, with one exception (Trujay), I avoided listing any vendors who don't publish prices. I included Trujay because no other vendor supported the wealth of CRM platforms they did.

Any final recommendations?

Yeah. Don't aim for perfection. Aim for good enough. Plan ahead to know what "good enough" means for your organization. I've found that there are always some edge-case records that muck up the works, and trying to get every single thing perfect just isn't practical. Be willing to manually enter or update a small number of records or delete a few that just aren't mission-critical. All this goes to planning. Scope out what you're dealing with, plan out how you're going to make the move, and decide what's important and what's absolutely mission-critical. Don't confuse mission-critical with just nice to have. Be patient. Be nice to the vendors. And communicate as clearly as you possibly can.

So what about you? Have you migrated cloud data? Have you been stuck on a cloud provider? Let us know in the comments below.

See also: 

You can follow my day-to-day project updates on social media. Be sure to follow me on Twitter at @DavidGewirtz, on Facebook at Facebook.com/DavidGewirtz, on Instagram at Instagram.com/DavidGewirtz, and on YouTube at YouTube.com/DavidGewirtzTV.

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