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Systems Administrator with Security Clearance
Castello Systems, Inc.Annapolis Junction, MD🇺🇸United StatesPosted 28 Jul 2026
Quick Overview
Work Type
Hybrid
Level
Mid Senior
Job Description
As a Tier II Help Desk / Systems Administrator, you will provide advanced technical support to enterprise users by diagnosing, troubleshooting, and resolving hardware, software, desktop, and cloud infrastructure issues. You will support users worldwide through remote support technologies while mentoring junior technicians and helping maintain operational excellence across the enterprise. Location: Annapolis Junction, MD Schedule: Full-Time Shift: Monday–Friday, 10:00 AM – 6:00 PM Training Schedule: Monday–Friday, 6:00 AM – 2:00 PM or 7:00 AM – 3:00 PM Clearance Required: Active TS/SCI with Full Scope Polygraph Responsibilities Provide Tier II technical support for desktop, network, hardware, and software issues.
Troubleshoot and resolve complex technical problems affecting enterprise users.
Provide remote support using Remote Desktop, desktop mirroring, and remote assistance tools.
Support users across worldwide enterprise locations.
Investigate, document, resolve, and follow up on help desk incidents involving cloud infrastructure and enterprise systems.
Apply structured troubleshooting methodologies to identify root causes and implement effective solutions.
Escalate complex issues when appropriate while maintaining ownership through resolution.
Install, configure, and support desktop hardware, peripherals, operating systems, and enterprise software.
Document incidents, resolutions, and technical procedures within the organization's ticketing system.
Assist with system maintenance, upgrades, and operational support activities.
Provide guidance and mentoring to junior support personnel.
Deliver exceptional customer service while maintaining compliance with security and operational procedures. Required Qualifications Active TS/SCI Clearance with Full Scope Polygraph.
Bachelor's degree and at least 10 years of relevant experience, or a high school diploma/GED with at least 15 years of relevant experience.
Experience providing Tier II technical support in an enterprise environment.
Strong knowledge of desktop hardware and troubleshooting.
Experience using Remote Desktop and Remote Assistance tools.
Experience supporting Windows desktop environments.
Strong analytical and problem-solving skills.
Excellent verbal and written communication skills.
Ability to work independently while supporting multiple priorities.
Strong customer service and interpersonal skills.
DoD 8570 IAT Level I certification.
CompTIA A+ CE and/or CompTIA Network+ CE (or equivalent certification meeting DoD 8570 requirements).
Preferred Qualifications Enterprise help desk experience
Systems administration experience
Cloud infrastructure support
Windows Server administration
Active Directory
Microsoft 365
Enterprise ticketing systems
Remote monitoring and management tools
ITIL experience
Experience supporting Department of Defense or Intelligence Community customers
Troubleshoot and resolve complex technical problems affecting enterprise users.
Provide remote support using Remote Desktop, desktop mirroring, and remote assistance tools.
Support users across worldwide enterprise locations.
Investigate, document, resolve, and follow up on help desk incidents involving cloud infrastructure and enterprise systems.
Apply structured troubleshooting methodologies to identify root causes and implement effective solutions.
Escalate complex issues when appropriate while maintaining ownership through resolution.
Install, configure, and support desktop hardware, peripherals, operating systems, and enterprise software.
Document incidents, resolutions, and technical procedures within the organization's ticketing system.
Assist with system maintenance, upgrades, and operational support activities.
Provide guidance and mentoring to junior support personnel.
Deliver exceptional customer service while maintaining compliance with security and operational procedures. Required Qualifications Active TS/SCI Clearance with Full Scope Polygraph.
Bachelor's degree and at least 10 years of relevant experience, or a high school diploma/GED with at least 15 years of relevant experience.
Experience providing Tier II technical support in an enterprise environment.
Strong knowledge of desktop hardware and troubleshooting.
Experience using Remote Desktop and Remote Assistance tools.
Experience supporting Windows desktop environments.
Strong analytical and problem-solving skills.
Excellent verbal and written communication skills.
Ability to work independently while supporting multiple priorities.
Strong customer service and interpersonal skills.
DoD 8570 IAT Level I certification.
CompTIA A+ CE and/or CompTIA Network+ CE (or equivalent certification meeting DoD 8570 requirements).
Preferred Qualifications Enterprise help desk experience
Systems administration experience
Cloud infrastructure support
Windows Server administration
Active Directory
Microsoft 365
Enterprise ticketing systems
Remote monitoring and management tools
ITIL experience
Experience supporting Department of Defense or Intelligence Community customers
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