PST Migration

PST Migration

The Issues

In today’s modern data messaging architecture, PST files are no longer a suitable storage medium within a corporate environment. PST migration helps to mitigate the risks associated with PST files that include:


Having no centralised management, a lack of enforceable retention policies, an insecure format and a high probability that they contain sensitive information, PSTs are highly likely to fail a GDPR compliancy test.


They are vulnerable to corruption, have limited potential for recovery and require specialist intervention, often resulting in a loss of data.

Costly to Store

With the uncontrolled nature of PST files, organisations often find multiple copies of the same PST littered around infrastructure, with each copy potentially being backed up on a daily basis. The cost of this can be enormous.



With the increased use of smart phones and other methods for web-based email access, data contained within PST files can be impossible to view as only Outlook can be used to open them.

The Solution

The only way to gain control of this unstructured data is to migrate the PST files to a centralised system such as Exchange, Office 365, Mimecast, EV.Cloud or one of the other numerous alternative archive providers. This provides centralised access as well as comprehensive search and reporting functionality. PST migration into a central repository can however be fraught with issues such as password protection, corruption, owner identification and files from staff who have left the organisation. Thankfully, help is at hand!

Automated Data Discovery

Owner Assignment

Complex algorithms and defined rules ensure integrity and accuracy of owner assignment. This minimises the risk of miss-assignment which is highly likely with manual methods.


With the potential of tens of thousands of files to locate, manual discovery is generally not an option. Our software can be configured to find PST files anywhere, even on workstations and laptops.

Distrubuted Architecture

The potentially geographically dispersed nature of PST files can be easily handled due to our distributed architecture. This allows the files to be located as quickly as possible and with minimal disruption.

Detailed Reporting

The discovery process analyses PST files for corruptions and collects data such as size, message count, password protection and location – all this is made available to allow detailed project planning.

Scheduled PST Migration

Built-in Connectors

Built in connectors ensure that the PST files are migrated directly to destinations such as Exchange, O365, Mimecast, EV.Cloud and many more.

Full Control

Built in scheduling, batch management and detailed control of message types and dates, plus comprehensive progress reporting provides full project control from start to finish.


Intelligent Error Handling

Intelligent error recovery and reporting ensures that issues are flagged up and handled with minimal user intervention and in a timely manner.

Multi Threading

Ensures that the migration is performed in the most effective way, reducing time and cost.

The Results

Once the PSTs have been migrated to a centralised system such as Exchange, Office 365, Mimecast or EV.Cloud, the data that was once inaccessible and unstructured is now held in a searchable and manageable central location. From here it can be tracked, is secure and significantly is GDPR compliant. Key deliverables include:


Complete Overview

A complete picture of your organisation’s PST file data


Secure and Compliant

Improved data storage security and ensured GDPR compliance

Cost Reduction

Reduced data storage costs

Automated and Auditable

Timely, cost-effective and compliant project delivery

PST Migration Steps

1) Locate the PST files

Discovery is a critical first stage of the PST migration process. While smaller companies may be able to locate all PST files manually, medium to large organisations with tens or even hundreds of thousands of PST files located on servers, workstations and laptops are likely to struggle. Not only would this be a thankless task, but manually assembling lists containing this volume of files is prone to human error. Moreover, many applications use the .PST file extension meaning that not all files with this extension actually contain messaging data and should obviously be ignored.

Our distributed architecture allows us to find files wherever they are located, be it centrally or hidden away in a regional office. PST Accelerator also checks that the file found is actually an Outlook file before adding it to our database, thus ensuring reports detailing your PST estate are accurate.

2) Assign owners

PST Accelerator uses complex algorithms to determine PST file ownership, taking many factors into account during the discovery process. Because the process is fully automated and allows one or more rules to be set, the possibility of miss-assignment is drastically reduced if not eradicated entirely.This provides confidence that the right file has been associated with the right individual, the PST migration will not place the messages in the wrong destination, and simplifies the project even further.

3) Scheduled PST Migration

The final stage is the PST migration itself, where the PST file is moved or copied into the destination. This can be done on a scheduled basis, is multi-threaded and can be to one of a number of destinations including Enterprise Vault, Microsoft Exchange, Office 365, or MimeCast to name but a few. We understand that issues might occur along the way during the PST migration such as corrupt messages, network issues between source and destination and space limitations. As a result, error handling is designed into the product from the ground up, with configurable retries, skipping and reporting of corruptions and the management of space quotas all built in as standard.


One issue that has surfaced recently is that of Subject Access Requests (SARs), where a company receives a request for information from an individual. In order to fulfil the request properly, the company must search all of its email communications, including PST files. These storage files can be searched from within Microsoft Outlook, but this does require someone to manually connect to each PST file in turn and then type in the search criteria. For small companies with a few employees this can be manageable, subject to understanding what terms to search for. However, for larger companies potentially with multiple offices, finding all PST files on the network can be troublesome. There have been instances where estimates have been given for 1 – 2 Tb of PST files only for our software to find in excess of 46.5Tb during the discovery process. And once the files have been found, the process of manually opening them is unlikely to be completed within the statutory timescales of 1 month. There have been instances of large corporations spending £300k – £400k in resourcing, simply to respond to a single SAR. The next SAR will cost the same again. A much cheaper option is to migrate the PST files to a central system such as Exchange, Office 365, Mimecast or EV.Cloud where enterprise grade search facilities exist.