**ManTech** is seeking a talented and experienced **Senior Systems Engineer** to join our team in **Herndon, VA.** **Duties, Tasks & Responsibilities:** + Provide Tier 3 and Tier 4 troubleshooting support for a wide range of server and network technologies. + Expertise in managing and supporting Microsoft CA (Certificate Authority), PKI (Public Key Infrastructure), and OSCP (Online Certificate Status Protocol). + Provide expert support and troubleshooting for Windows Server 2016, 2019, and newer versions. + Manage and support Active Directory, DNS, and DHCP systems. + Work extensively with cloud technologies, demonstrating in-depth knowledge and hands-on experience. + Develop and execute PowerShell, VB, and C# scripts to automate and enhance system operations. + Prioritize and execute tasks effectively in a high-demand environment, managing multiple initiatives simultaneously. + Collaborate with internal teams or work independently to resolve issues and complete projects efficiently. + Continuously adjust to and learn new technologies as they arise. + Write enterprise-level technical standards documentation, including diagrams and process workflows. + Provide high-quality customer service and support to internal teams and clients. **Required Education, Experience, & Skills:** + 16+ years of relevant experience in Systems Engineering/Information Technology + Bachelor's Degree in relevant Information Technology, Computer Science, or related field. + In-depth knowledge and hands-on experience with Microsoft Certificate Authority (CA), PKI, and OSCP. + Strong troubleshooting skills at Tier 3 and Tier 4 levels. + Expert experience with Windows Server OS 2016, 2019, and above. + Advanced knowledge of Active Directory, DNS, and DHCP. + In-depth knowledge and experience working with cloud technologies. + Proficiency in scripting languages such as PowerShell, VB, and C#. + Ability to effectively prioritize tasks and meet deadlines. + Strong ability to work independently and as part of a team. + Ability to learn and adapt to new technologies quickly. + Experience in writing and maintaining enterprise-level technical standards documentation and system diagrams. + Excellent customer service skills. **Preferred Skills:** + Master's Degree preferred in relevant Information Technology, Computer Science, or related field. + MCSE (Microsoft Certified Solutions Expert) or MCITP (Microsoft Certified IT Professional) certification. + Experience with Microsoft Azure Pack. + Experience with Amazon Web Services (AWS). + Advanced proficiency with PowerShell scripting. + Understanding of enterprise networking best practices. **Security Clearance Required** + An active TS/SCI with Polygraph. **Physical Requirements:** + Ability to operate office machinery, such as a computer, printer, and phone systems. + Ability to sit or stand for extended periods of time while working at a desk. + Ability to move within the office and access files or equipment as needed. ManTech International Corporation, as well as its subsidiaries proactively fulfills its role as an equal opportunity employer. We do not discriminate against any employee or applicant for employment. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, or status as a protected veteran. If you are a qualified individual with a disability and require a reasonable accommodation to apply for a position with ManTech through its online applicant system, please email us at careers@mantech.com and provide your name and contact information.