Global Legal Firm Migrates HP EAs Exchange Archives to Microsoft 365 

Background 

Headquartered in the US, this global insurance firm is known for its strength in the energy, financial services, real estate, and retail and consumer product industries. It also has an expanding global privacy and cybersecurity practice. 

For over a decade, the firm had relied on HP Email Archiving software for Microsoft Exchange (HP EAs Exchange), a dedicated on-premises email archive for Microsoft Exchange, to manage its email retention and prevent its on-premises Exchange servers from being overloaded. 

Part of the HP portfolio alongside HP Integrated Archive Platform (IAP), HP EAs Exchange provided the firm with crucial features such as robust storage capacity, comprehensive lifecycle management, and advanced eDiscovery capabilities. 

Essential Computing, one of the first email archiving specialists in the world, had completed the firm’s original implementation of the archive back in 2001. An in-depth knowledge of the product and the experience gained from implementing over 500 migration projects convinced the customer that Essential would be the best partner to work with to address its new challenge – a migration away from HP EAs Exchange. 

The Migration Challenge 

The customer had over 2,000 active users whose mailboxes had been migrated from Exchange on-premises to Microsoft 365. 

While users could still access their archived emails through inbox shortcuts that operated across the network, this setup had become unsustainable:  HP EAs Exchange had reached its end of life and was no longer supported, introducing a significant risk to the business. Additionally, the on-premises implementation of the archive was misaligned with the firm’s broader cloud strategy. 

An email archive migration was needed to fully and reliably replace these shortcuts with the original email and any attachments that were in the archive, allowing the archive to be decommissioned. 

“We refer to the process of replacing shortcuts with the original email as ‘rehydration’.  The end result is as though the email was never archived in the first place.” 

Explained Annie Holder, the migration specialist leading this project

Migrating Extra Large Emails & Mailboxes 

Being a law firm it was no surprise that there were some very large mailboxes and large emails with big attachments that needed to be ‘rehydrated’ into Microsoft 365.   

Although Microsoft 365 mailbox quotas are generous, rehydrating shortcuts without first checking the end results might compromise users’ mailbox quotas. The sheer volume of emails being restored might also make historic emails difficult for users to find. 

This and other migration considerations specific to the firm were thoroughly discussed, and test migrations were conducted as part of the migration planning process. 

To address the size issue, larger mailboxes had just the most recent years’ worth of emails rehydrated into the users’ primary mailboxes.  Emails older than 1 year were split up and migrated into appropriately named folders (1-year, 2-year, 3-year, or 4-year) to make it easy for users to find legacy emails without being overwhelmed.  Any emails older than 4 years were then migrated to the users’ In-Place archive – an archive service offered natively in Microsoft Exchange online. 

Even with this approach, the amount of email directed to the In-Place archive sometimes exceeded the initial 90GB allocation. This necessitated enabling Microsoft’s archive auto-expanding service, which automatically adds more storage to the In-Place archive until a limit of 1.5 TB is reached.  

Since it can take up to 30 days or longer for this additional storage space to be provisioned, Essential configured the HP email archive migration to automatically retry on a daily basis.  

Any shortcuts to archived emails that had already been migrated into Microsoft 365 as part of the initial mailbox migration were also removed during the migration process to ensure a clean, tidy mailbox for all users. 

Working with Essential 

Explained Holder, “The relationship with the customer was very good and the customer’s technical contacts were excellent. This contributed to a successful project completed within 6 months* and a happy customer. 

Despite Essential being based in the UK and the migration physically taking place in the US, this posed no issues whatsoever. In fact, it offered the advantage of Essential being able to oversee and ramp up migration activities outside of core office hours, allowing any issues that required client input to be reported and addressed first thing their next working day. 

*As a side note, the project could have completed in 4 months if Microsoft was quicker to extend archives where the quota limit was reached. In the event, it took up to 6 weeks for some mailboxes’ archives to be auto-extended.