Whether it's outdated Windows 7 machines, even older XP systems, or tools like Microsoft Project – many organizations still rely on technologies that are no longer up to current standards. The same applies to specialized applications that haven’t received updates or support in years, yet continue to play a role in day-to-day operations, across public authorities, law firms, research institutions, and businesses.
These so-called legacy systems have often been in use for years. They’re seen as reliable and stable. In reality though, they carry significant risks and increasingly limit an organization’s ability to act.
As technology evolves at a rapid pace, outdated IT structures are falling further behind. Holding on to them for too long increases the risk of technical problems and serious security issues. This article explores what defines a legacy system, why such systems remain so widespread and how organizations can transition away from them gradually and effectively.
What is a legacy system?
Legacy systems refer to outdated but still operational hardware and software. This includes unsupported servers, computers or operating systems as well as industry-specific applications. A legacy system might be a mainframe from the 1990s or a business-critical tool that only runs on Windows XP. The term covers both hardware and software that technically still work but no longer meet modern standards.
On the hardware side, this often includes old terminals, servers, or underpowered desktops and laptops. While cloud adoption has reduced the use of local hardware in recent years, many organizations still rely on their outdated equipment, trusting in its familiarity and supposed reliability.
The software side tends to be even more challenging. The risks grow when systems or applications are used that no longer meet today’s requirements for security or data protection. Prominent examples include the older Microsoft operating systems mentioned above, which no longer receive updates, or products like Microsoft Project or Teams, whose use in sensitive environments has become questionable, not just technically but also politically.
Why are legacy systems still in use?
Legacy systems are common across industries, especially where processes have evolved over time and been tailored to specific needs. The reasons for continuing to use them vary:
Assumed reliability and functionality:
Many legacy systems appear to work reliably in day-to-day operations. They are deeply integrated into workflows and have proven themselves over time. Changing them often seems riskier than maintaining the status quo.
Cost and resource concerns:
Replacing an old system involves effort – technical, financial, and organizational. With limited budgets or capacity, migrations are often delayed or avoided altogether.
Dependencies and knowledge gaps:
Custom-built applications are rarely easy to replace with standard tools. Many organizations are locked into specific ecosystems due to vendor lock-in. Documentation is often incomplete or missing entirely. Key knowledge lives in the heads of a few long-serving staff and can easily be lost.
Regulatory and certification barriers:
In heavily regulated industries like finance or healthcare, system changes often require extensive audits and recertifications. This adds another layer of complexity to any transformation effort.
Worry about change:
New tools aren’t always seen as helpful. Without proper communication and onboarding, teams often respond with hesitation – but not necessarily out of rejection, but due to uncertainty. Concerns around complexity, time investment, or disruption to established workflows are widespread.
Common risks and challenges
Legacy systems may feel stable in the short term. But over time, they become a liability:
- Security vulnerabilities
Without ongoing vendor support, systems no longer receive updates. Known weaknesses remain open and increase the risk of attacks, including ransomware or data breaches.
- Rising operational costs
Specialized maintenance, custom workarounds, and additional security layers require time and money. Combined with vendor lock-in, this leads to high ongoing expenses.
- Lack of compatibility
Modern tools and cloud services are hard to connect to legacy systems. This causes manual work, data silos, and broken workflows, especially in hybrid work environments.
- Limited scalability
Even small changes, like adding user groups or enabling two-factor authentication, can demand major effort. As a result, innovation is often postponed or blocked entirely.
- Data protection and compliance risks
Many legacy systems lack features like role-based permissions, deletion workflows, or end-to-end encryption like Stackfield. As a result, compliance with regulations such as the GDPR becomes difficult or impossible.
Practical ways forward
Not every organization can or should replace its legacy systems all at once. A more realistic path is to modernize step by step, with a clear strategy. Three common approaches are rehosting, refactoring, and replacing:
Rehosting: With rehosting, an existing system is migrated to a new technical environment. A typical example is moving a legacy application from an old physical server to a virtual machine in the cloud. The software itself remains unchanged but benefits from improved stability and scalability thanks to the modern infrastructure.
Refactoring: Refactoring involves restructuring the system's source code to make it more maintainable and flexible. The core functionality stays the same, but the architecture is updated, making future enhancements and integrations much easier.
Replacing: Replacing means retiring the legacy system and switching to a new software solution that performs similar or equivalent tasks. This approach doesn’t just bring a technical upgrade, it also improves usability, increases security and introduces a modern, future-ready framework. Moving from an outdated collaboration tool to Stackfield would be a good example of this.
Stackfield as a Practical Solution
A full system replacement isn’t always the right first step. Often, it’s more effective to introduce a new solution gradually – for example, within a single team or department.
Stackfield is well-suited for this type of parallel setup. Key functions like task management, communication, and file sharing can be implemented right away, without disrupting existing workflows. Data such as documents, spreadsheets, and tasks can be imported selectively – for example by directly importing CSV/Excel files. The intuitive interface makes onboarding easy and reduces the need for extensive training. Information is no longer tied to individuals but is managed centrally and made accessible to everyone who needs it.
Another key advantage is data protection. Stackfield is specifically built for the European market, is ISO-certified, carries the C5 attestation from the German BSI, and stores all data end-to-end encrypted on servers located in Germany.
Instead of a disruptive reset, this approach enables a smooth transition. The legacy system can remain in place initially, while a modern, reliable alternative is introduced step by step. This creates flexibility and reduces operational risk.
Conclusion: Moving on from legacy systems step by step
Many organizations have been using the same systems for years. That may offer a sense of reliability, but it also means that problems and risks often go unnoticed until it’s too late. Delaying the switch increases the likelihood of security issues, rising costs, and a loss of control over core IT processes.
Still, legacy infrastructure rarely disappears overnight. With solutions like Stackfield, however, a clear and gradual transition is possible. Existing workflows can continue, while new structures take shape. That reduces pressure, creates room to maneuver, and makes organizations more flexible in the long term.