How CT Assist built a reliable cold outreach engine – while saving its main domain

About CT Assist

Industry: Healthcare staffing / Staffing and Recruiting

CT Assist is a US-based healthcare staffing firm that places locum tenens physicians, advanced practice providers, and clinical professionals with hospitals and health systems across the country.

Email is central to the business – used for communicating with active providers, engaging client health systems, and reaching hard-to-find clinical talent. With a recruiter team operating at scale, reliable inbox placement directly determines whether the right clinicians see the right opportunities.

The problem: everything mixed on one domain

By early 2025, CT Assist’s email program had effectively broken down. Cold outreach attempts, bulk campaigns, and ongoing client communication were all running through the same sending infrastructure. The combined sending behaviour damaged the company’s sender reputation – landing the team in what they described as “email jail,” particularly with Yahoo and AOL.

The symptoms were hard to miss:

Spam complaints from candidates	Recruiters regularly heard: “I found your email in spam.” Internal inbox tests confirmed the same.
Bounce rates reaching 8.3–8.4%	During peak sending periods, bounces climbed sharply forcing the team to cut volume to avoid further damage.
Client replies going to spam	The real turning point: mid-thread replies from existing clients began landing in spam. The main domain itself was compromised.

“The real wake-up call was when even our normal replies to clients started dropping into spam in the middle of ongoing threads. At that point, it was clearly more than just ‘our open rate is a bit low.”

CT Assist recruiting leadership

Why DIY wasn’t enough

CT Assist first tried to fix the problem in-house. They purchased new domains, ran warm-up sequences, and waited. It didn’t work – test emails from those new domains were still landing in spam.

The result made clear this required genuine deliverability expertise, not another warm-up tool. When evaluating options, two Folderly capabilities stood out:

Real-time inbox placement visibility across all major mailbox providers, with spam trigger flags and best-practice alerts.
Specific, expert guidance – a team that could assess CT Assist’s situation and give concrete next steps, not generic advice about subject lines.

“Deliverability used to feel like a black box. Now people understand why templates eventually ‘burn out,’ why the first email in a sequence needs to be as clean as possible, and what to do when a spam trigger pops up. It isn’t on one person to fix everything anymore.”

CT Assist recruiting leadership

The solution: two-track email infrastructure, built from scratch

Folderly and the CT Assist team didn’t patch the existing setup, they rebuilt it. The goal was to protect the main domain for client communication while creating a separate, properly structured system for outreach that hadn’t existed before.

Challenge	Solution
Domain and mailbox separation	Cold outreach was fully moved onto dedicated outreach domains and mailboxes, completely separate from the main company domain. This protected the primary domain’s reputation and created a clean foundation for prospecting activity.
Structured mailbox preparation	Each new mailbox followed a controlled preparation plan – including a structured warm-up – before any real sending began. This ensured domains were fully ready before volume ramped up, rather than burning out within days.
DNS and authentication alignment	Folderly reviewed and corrected SPF, DKIM, and DMARC configuration across all sending domains, establishing the authentication foundation required for sustainable inbox placement.
Template and content overhaul	First-touch templates were audited and rebuilt – removing broken symbols, cleaning up spam-trigger language, and restructuring content to meet deliverability standards for large-scale outreach in a regulated category.

Results

The improvements were measurable within weeks of implementation.

Folderly Results CT Assist

Beyond the numbers: a team that understands deliverability

The larger shift at CT Assist has been cultural. Deliverability used to be a black box – something one person would try to fix when things broke. Deliverability used to be a black box. Something one person would try to fix when things broke. Now the whole team understands why templates eventually burn out, why the first email in a sequence needs to be clean, and what to do when a spam trigger appears.

With Folderly monitoring inbox placement in real time and a dedicated CSM interpreting the data, the recruiting team can build outreach plans around hiring pushes, new specialties, or major searches without wondering whether their emails will actually be seen.

“If you rely on email to reach busy clinicians and clients, finding out your domain is in ‘email jail’ is a nightmare. Folderly helped us protect our main domain, build a smarter outreach setup on new domains, and give our recruiters a clear, repeatable process for staying in the inbox. Email feels like a reliable growth channel again, not a liability.”

– CT Assist recruiting leadership