Onsite Client Engineer (Essex, Hertfordshire, Suffolk, Kent & West Sussex)

About Arc:
Arc is a leading IT Managed Services Provider (MSP) based in the UK, delivering innovative and reliable IT solutions to businesses across various industries. With a strong reputation for excellence, we offer a range of services, including IT support, hybrid cloud solutions, cybersecurity, infrastructure management, PowerApps and AI. Our team is dedicated to delivering outstanding customer service and technical expertise to help businesses succeed.

Role Overview:
Arc Systems is a UK managed service provider supporting businesses across the South East and beyond. We're looking for an experienced Onsite Client Engineer to become the embedded technical presence for one of our key multi-site client accounts.

This is a genuinely varied role that goes well beyond standard desktop support. You'll own day-to-day onsite and remote support across a group of client sites, but you'll also run the account's mobile and telephony estate, manage its Microsoft 365 and Intune environment, support SQL-based data workloads, and provide the technical muscle behind acquisitions and business projects. You'll be trusted, visible, and the person the client turns to first.

You'll replace a well-regarded engineer who is moving on, with a structured handover to get you established on the account.

Key Responsibilities:

Onsite & end-user support

• Hands-on break/fix support across the estate: laptops, printers, presentation screens, visitor tablets and general end-user hardware.

• Working the internal support queue, plus dedicated queues for new starters and mobile issues.

• Providing onsite assistance to third-party installers (e.g. EV car chargers, CCTV), including allocating IP addressing and network access.

Starters, leavers & assets

• Owning the new starter process end to end: creating user accounts, arranging and configuring equipment, and assigning assets in the client's asset system (Focal Point).

• Running the user retention process: weekly reporting on accounts disabled for 60+ days and actioning deletions.

Mobile & telephony

• Managing the mobile estate: resolving SIM and device issues via the O2 portal and liaising with the provider on escalations, including a standing weekly review call.

• Supporting the client's Asterisk-based phone system (SARK): configuring new PBX tenants for acquisitions, setting up CDR report emails, and engaging the telephony support partner on complex work.

Microsoft 365, security & MDM

• Managing MDM through Intune and Apple Business Manager: building and deploying policies across the device estate.

• Configuring SSO for new business applications and maintaining Conditional Access policies.

• Firewall configuration and changes (Sophos XG).

• Producing security and compliance reporting from Microsoft 365 and Sophos for the client's Security Manager.

SQL & data

• Investigating SQL Server performance issues, including blocking queries and deadlocks.

• Running the data transfer process for new acquisitions: provisioning SFTP accounts, building SQL SSIS import/export packages, and creating and scheduling the associated jobs.

• Setting up SFTP accounts for external file transfer partners (e.g. banking and service providers).

Projects & stakeholders

• Liaising with third-party vendors on ongoing projects (Focal Point, IFS, ClickLearn and others), including regular project meetings.

• Providing technical assistance to the client's ERP/Systems team when implementing new solutions.

• Attending weekly internal IT team meetings covering ongoing projects and acquisition activity.

Site Coverage

The role is field-based with regular travel across the client's sites. A full UK driving licence and your own vehicle are essential (mileage paid). Typical coverage:

The role is field-based with regular travel across the client's sites. A full UK driving licence and your own vehicle are essential (mileage paid). Typical coverage:

• Rainham- At least once a week

• Waltham Cross- At least once a week

• Stowmarket- Monthly on average; weekly at busier times

• Rochford- Monthly on average; weekly at busier times

• Tunbridge Wells- Monthly

• Knebworth- As required

• Chichester- As required

• Risby- As required

Visit frequency flexes with business need — new acquisitions or projects can temporarily increase visits to any site. Remote work is completed from home or a local site between visits.

Visit frequency flexes with business need — new acquisitions or projects can temporarily increase visits to any site. Remote work is completed from home or a local site between visits.

Required Skills & Experience:

Essential

• Solid 2nd/3rd line experience in an MSP or multi-site environment, comfortable being the sole IT presence on a client site.

• Strong Microsoft 365 administration: Entra ID, Intune, Conditional Access and SSO configuration.

• Confident end-user hardware and peripherals troubleshooting (Windows laptops, printers, meeting room AV, tablets).

• Networking fundamentals (IP addressing, VLANs, DNS/DHCP) and hands-on firewall experience.

• Working knowledge of SQL Server, with the aptitude to diagnose performance issues.

• Excellent communication — you'll be client-facing daily and dealing with vendors, providers and senior stakeholders.

• Well organised across multiple queues, sites and priorities, with a full UK driving licence and own vehicle.

Desirable

• Sophos XG firewall experience.

• SQL SSIS package development and job scheduling.

• VoIP/Asterisk-based PBX experience.

• Apple Business Manager administration.

• Experience supporting business acquisitions, migrations or onboarding of new sites.

What We Offer:

• Competitive salary (dependent on experience) plus paid mileage for site travel.

• A varied, high-trust role with genuine ownership of a key client account.

• Exposure to a broad technology stack — from M365 and security through to SQL, telephony and networking — with training and development supported.

• A structured handover from the outgoing engineer and the backing of Arc's wider service desk and engineering teams.

Key Points:

Diversity & Inclusion: We celebrate diverse backgrounds and perspectives; they make us stronger. If you’re excited about this role, apply even if your experience doesn’t align perfectly. If not this one, you could be just the right fit for other roles we are recruiting for. We are an equal opportunity employer and value diversity at our company. We do not discriminate on the basis of race, religion, colour, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.

UK Right to Work: All applicants must have the right to live and work in the UK. We cannot offer sponsorship at this time.

Accessibility: We are committed to providing reasonable adjustments for any candidates with disabilities. If you require adjustments, please outline these requirements in your application.