Third-party patching is one of those things that sounds simple until it isn’t.

Most MSPs have some form of it in place, whether through their RMM, scripts, or add-ons. But when you look closer, there are consistent gaps that create risk, inconsistency, and operational headaches.

In this blog, we’ll walk through the most common mistakes MSPs make with third-party patching and what to do instead.

Assuming It Works Like Windows Update

One of the biggest misconceptions is that third-party patching behaves like Windows Update.

It doesn’t.

Microsoft controls the Windows update ecosystem; packaging, delivery, installation logic, and rollback behavior are standardized. Third-party applications are the opposite. Every vendor handles updates differently, with varying install methods, silent switches, reboot requirements, and failure conditions.

Treating third-party patching like Windows patching results in unreliable outcomes and gaps in coverage.

What to do instead:

Approach third-party patching as its own process. It requires validation, visibility, and control at the application level—not just a checkbox in an RMM.

Not Treating LoB Apps the Same Way as Other Applications

Line-of-business (LoB) applications often get special treatment, and not in a good way.

They’re frequently excluded from automated patching because they’re considered “too important” or “too risky” to touch without manual oversight. As a result, they fall behind on updates and become some of the most vulnerable systems in the environment.

Attackers don’t distinguish between “standard” apps and “critical” ones. If anything, LoB applications are more attractive targets.

We’ve seen how quickly vulnerabilities can be exploited, sometimes within hours of disclosure.

What to do instead:

LoB applications should be part of a structured patching process with testing and controlled deployment, not excluded from it.

Assuming an Add-On Will Magically Take Care of Everything

Many MSPs rely on third-party patching add-ons within their RMM and assume the problem is solved.

In reality, most add-ons:

• • Support a limited set of applications

• • Lack of granularity for exclusions and edge cases

• • Provide limited insight into patch success or failure

They can be helpful, but they don’t replace a proper patching strategy.

What to do instead:

Understand the limitations of add-ons. Patching requires more than deployment; it requires consistency, granularity, and a system that ensures patches actually succeed.

Focusing Only on Security (Forgetting Support Impacts)

Patching is often framed purely as a security function.

While security is critical, it’s not the only consideration. Poorly managed patching can introduce application issues, downtime, and support tickets, especially at scale.

This creates tension between security and operations:

• • Patch too slowly → increased risk

• • Patch too aggressively → increased support burden

What to do instead:

Balance security with operational stability. Aim for repeatable rollouts, testing groups, and rollback functionality to ensure patches don’t create downstream issues.

Thinking RMM Scripts Will Scale

Custom scripts are a common approach to third-party patching.

They work well initially, but they don’t scale.

As environments grow, scripts become:

• • Difficult to maintain

• • Inconsistent across clients

• • Time-consuming to troubleshoot

What starts as a flexible solution often turns into technical debt.

What to do instead:

Move away from script-heavy patching strategies as you scale. Standardization and repeatability are key to maintaining consistency across environments.

The Pattern Behind These Mistakes

All of these issues point to a common theme:

Third-party patching is being forced into tools and workflows that weren’t designed for it. And in today’s landscape, that approach doesn’t hold up. Exploits are moving faster, attack surfaces are expanding, and support needs are increasingly focused on third-party applications.

The Fix for Common MSP Third-Party Patching Mistakes: ThirdPatch

ThirdPatch was built specifically to address these common MSP third-party patching mistakes.

Instead of relying on scripts or limited add-ons, it provides a structured approach to third-party patching that aligns with how applications actually behave.

With ThirdPatch, MSPs get:

• • Broad and purpose-built application coverage

• • Reliable deployment workflows

• • Visibility into patch status and outcomes

• • A scalable system that removes the need for custom scripting

ThirdPatch for MSPs

ThirdPatch is designed for MSPs who want to take control of third-party patching without adding operational overhead.

It replaces fragmented approaches with a consistent, scalable solution that works across environments.

If you’re relying on scripts, add-ons, or inconsistent processes today, ThirdPatch provides a clear path forward.

You can learn more about ThirdPatch here.