Application allowlisting protects a contractor’s machines by only letting approved software run and blocking everything else by default. Using a tool like ThreatLocker, that means ransomware, malware and unknown programs simply cannot execute, even if someone clicks the wrong thing. For a firm that handles payments and client sites, it’s one of the strongest, most practical protections you can have.
Most security tries to spot what’s bad. Allowlisting flips that around: it only permits what you’ve approved. Here’s why that suits a contractor.
1. It blocks ransomware before it runs
Ransomware has to run a program to encrypt your files. If only approved software is allowed, it never gets to start, which is a far stronger position than relying on detection alone to catch brand-new threats.
2. It limits the damage of a wrong click
Even careful people occasionally click a bad link or attachment, and contractors receive a lot of email from clients and suppliers. With allowlisting in place, a mistake is far less likely to turn into an incident, because the malicious program can’t execute.
3. It keeps machines clean and consistent
Allowlisting also stops unapproved software creeping onto work machines, which keeps your office and site devices secure, consistent and easier to support. You decide what runs on your firm’s computers.
4. It’s managed, not a burden
The worry with allowlisting is that it gets in the way. Done properly, it doesn’t. We manage the approved list for you, so your normal software runs smoothly while everything unknown stays blocked, and we approve new tools quickly when your team needs them.
A real example: an unknown program stopped
We support a security and M&E contractor where, when a previously unseen program tried to launch on a hosted desktop, application control blocked it automatically and raised it for review. We assessed it, approved the legitimate business tools, and left genuinely unknown code blocked, turning “everything runs unless we catch it” into “nothing runs unless we approve it.”
For most building-services and M&E contractors, this sits within fully managed IT at about £45 to £100 per user per month, billed per user, with the security and on-site remote access your teams need built in.
Why security and M&E contractors choose First Stop IT
First Stop IT has supported businesses since 2002, including security, fire and M&E contractors and building-services firms with office and site-based teams. We know how these businesses run: hosted desktops for staff on site and in the office, QuickBooks and payroll, secure remote access for field engineers, Microsoft 365 and Google Workspace, and the layered security that protects a firm handling client sites and payments, from MFA and application allowlisting to managed threat detection. We support contractors in Harlow, Bishop’s Stortford and across Essex, Hertfordshire and London. Our credentials include:
- Cyber Essentials Certified
- IASME Cyber Assurance (Gold)
- NCSC Assured Service Provider (Cyber Advisor for Cyber Essentials)
- Microsoft Partner
- Crown Commercial Service Supplier (G-Cloud)
- Quality Principles Certified
We look after more than 2,000 endpoints across 50 companies, we’ve been named a Top 50 UK MSP for three years running, and we support organisations with 10 to 100 employees across Essex, Hertfordshire and London, including Harlow and Bishop’s Stortford.
Book a free IT and cyber security review
Want ransomware blocked before it can run? Book a free IT and cyber security review with First Stop IT and we’ll show you how allowlisting protects your firm.