DSM 7.4.1 Problems: Drive, UPS & Package Fixes

Synology

Synology DSM 7.4.1-90080 arrived on July 23, 2026 as a relatively small maintenance update, but small DSM updates can still create big questions when a NAS contains third-party drives, USB UPS hardware, older packages, or years of customized configuration. For many users, the update has been uneventful. Community reports include successful upgrades on systems such as the DS1525+, DS220+, and other DiskStation models without immediate problems.

Others have encountered drive warnings, USB peripheral problems, packages requiring attention, or confusion about why DSM 7.4.1 is not being offered automatically. The important point is not to assume that every problem appearing after the update has the same cause.

Some issues were inherited from DSM 7.4 and specifically fixed by 7.4.1. Others involve compatibility policies rather than failing hardware. And some reports remain individual cases that should not be interpreted as universal DSM bugs. Here is what Synology administrators should check.

First, Know Exactly Which DSM Version You Installed

The current maintenance release discussed here is:

DSM 7.4.1-90080

Synology released it on July 23, 2026. The update requires a restart, and Synology warns that once DSM 7.4.1 has been installed, users cannot perform a normal downgrade to an earlier DSM release. That makes pre-update preparation particularly important.

Before installing a DSM release on a production NAS, administrators should verify:

Storage pool health
Current backups
Package compatibility
External devices
UPS operation
Critical scheduled tasks
Remote access
Snapshot and replication status

For business environments, upgrading every NAS simultaneously is rarely necessary. Updating a less critical system first can reveal compatibility problems before they affect the entire environment.

Why Isn’t DSM 7.4.1 Appearing on My NAS?

This has confused some users. DSM 7.4.1 is being distributed through a staged rollout, and Synology has also identified numerous older models that will not receive the update notification through DSM.

That list includes familiar Plus models such as:

DS918+, DS718+, DS218+, DS1618+, DS1817+, DS1517+ and RS1219+

among others.

For these systems, Synology says users can obtain the appropriate upgrade patch through the Synology Download Center if they specifically want to install it. So if Control Panel says your NAS is current but you know DSM 7.4.1 exists, do not immediately assume something is wrong. Check Synology’s release notes and Download Center for your exact NAS model before attempting a manual update.

The USB UPS Problem Is More Complicated Than It Looks

One of the most discussed DSM 7.4 problems involved USB-connected UPS devices. After upgrading to the original DSM 7.4 release, some users discovered that their previously functioning UPS was no longer recognized. Synology acknowledges this directly.

The official DSM 7.4.1 release notes state that the update:

fixed an issue where a USB UPS could not be recognized after updating to DSM 7.4.

It also fixed a separate problem where USB devices could not be used on certain NAS models following the DSM 7.4 upgrade. That makes upgrading from 7.4 to 7.4.1 an obvious first troubleshooting step if your UPS disappeared after installing DSM 7.4.

But Some Users Still Report UPS Problems on 7.4.1

Installing 7.4.1 does not guarantee that every USB UPS model will work. For example, one recent community report describes a CyberPower BU650EU that stopped being recognized after a DS220+ was upgraded to DSM 7.4.1-90080, even though it had worked immediately beforehand. That is useful evidence, but it should be interpreted correctly. A single report does not establish that DSM 7.4.1 universally breaks CyberPower UPS devices. The UPS in that report was also not on Synology’s tested compatibility list.

If your UPS remains undetected after 7.4.1, check:

1. Physical USB connection

Disconnect and reconnect the USB cable and verify the cable itself.

2. NAS restart

Restart after confirming DSM 7.4.1 is fully installed.

3. UPS status

Verify that the UPS itself is functioning normally.

4. Compatibility

Check Synology’s compatibility information for the NAS and UPS.

5. DSM detection

Open the UPS settings and determine whether DSM recognizes the device at all.

If a previously supported configuration still fails, document the NAS model, UPS model, DSM version, and previous working DSM version before opening a Synology support case.

Test the UPS Don’t Just Look for Its Name

Recognition alone is not enough.

After a DSM upgrade, perform an actual controlled UPS test.

Confirm that DSM can:

Detect the UPS
Read its status
Respond to loss of AC power
Enter the configured safe mode
Send expected notifications

Do not discover during a real outage that DSM displays the UPS correctly, but your shutdown policy no longer behaves as expected. For a business NAS, UPS functionality is part of disaster prevention and should be included in post-update validation.

What About “Unverified” Drive Warnings?

Drive warnings remain one of the most confusing Synology topics because hardware compatibility policy has changed substantially across DSM versions and NAS generations. An Unverified label does not automatically mean a disk is physically failing. It can indicate that the drive is not included in the compatibility database for that particular NAS configuration. That distinction matters. A drive can have perfectly normal health indicators while DSM simultaneously warns that the configuration has not been validated by Synology.

Before replacing a disk, determine whether you are looking at:

a compatibility warning

or:

an actual drive-health warning.

They are not the same problem.

Don’t Replace a Healthy Drive Just Because the Label Changed

If a drive suddenly appears differently after an update, start by checking Storage Manager.

Look at:

Storage pool status
Volume status
Drive health
S.M.A.R.T. information where available
Bad sector history
I/O errors
Drive reconnection events
Compatibility status

If the storage pool is healthy and the only concern is an Unverified compatibility designation, replacing the drive immediately may be unnecessary.

However, compatibility warnings should not simply be ignored in business environments either. Synology’s tested-drive lists exist to define configurations the company has validated and supports. The appropriate response depends on the model, drive, workload, support requirements, and whether the system is business-critical.

Be Careful With Community Scripts That Remove Drive Warnings

A number of community scripts and manual configuration edits exist for modifying Synology’s drive compatibility behaviour.

They can make unsupported drives appear differently or suppress warnings. But that does not turn an untested drive into a Synology-validated drive. It can also create another maintenance dependency. A DSM update may overwrite configuration changes or alter the underlying compatibility system. If you rely on an unofficial modification, document it before upgrading.

After the upgrade, verify whether it is still present and whether the script itself remains compatible with the new DSM release. For production environments, unsupported modifications should be treated as deliberate technical debt rather than invisible permanent fixes.

Check the Drive Compatibility Database Too

Synology maintains drive compatibility information separately from the basic DSM installation.

Its Download Center also provides the Synology HDD/SSD Offline Update Pack, which can update drive compatibility information and Synology drive firmware when the NAS cannot connect to the internet. This matters particularly for isolated business NAS systems. If drive status appears unexpectedly after an upgrade, verify that the compatibility database itself is current before assuming DSM has detected a new physical problem.

Snapshot Replication Requires Attention During 7.4.1

Synology specifically calls out Snapshot Replication in the DSM 7.4.1 installation notes. The package may be automatically updated or require a manual update to a compatible version. If your NAS uses snapshots for ransomware recovery, replication to another Synology, or business continuity, do not consider the DSM update complete merely because the desktop loads successfully. Open Snapshot Replication afterward.

Confirm:

The package starts normally
Existing snapshot schedules remain enabled
Replication tasks are healthy
Destination systems remain connected
Retention policies remain correct
Recent snapshots are actually being created

A package being installed is not the same as its protection jobs being operational.

Check Every Business-Critical Package After the Upgrade

The same principle applies beyond Snapshot Replication. A NAS may boot successfully while an application has stopped, requires an update, or behaves differently. Review the packages your organization actually depends on.

That might include:

Active Backup for Business
Hyper Backup
Synology Drive Server
Snapshot Replication
Surveillance Station
Container Manager
Virtual Machine Manager
Active Insight
Third-party packages

Open Package Center and look for packages requiring updates, repair, or manual action. Then test the actual service.

For example, don’t simply confirm that Hyper Backup launches. Verify that its most recent backup job completed successfully.

Third-Party Packages Deserve Extra Caution

Community and third-party packages may not follow Synology’s DSM release schedule. An application can work perfectly on DSM 7.3 and fail after a major DSM change because of modified libraries, permissions, APIs, or dependencies.

Before upgrading a NAS that relies on third-party packages, check whether the package maintainer explicitly supports DSM 7.4. If the package is essential to the business and the maintainer has not validated the new DSM version, waiting can be more sensible than being the first production deployment to test it. This is especially important because DSM 7.4.1 does not provide a normal downgrade path.

Container Users Should Test More Than Container Manager

A running Container Manager interface does not guarantee that every containerized application is healthy.

After updating, check:

Container state
Storage mounts
Network connectivity
Environment variables
Database connectivity
Reverse proxies
Scheduled container tasks
Application logs

A container can show as “running” while the application inside it is unable to reach its database or storage path.

Test services from the user’s perspective.

KMIP Users Have an Additional 7.4.1 Change

Businesses using KMIP need to pay particular attention to DSM 7.4.1. Synology changed KMIP certificate handling to comply with updated certificate issuance policies. KMIP client authentication now requires certificates issued by a private certificate authority.

Synology states that its default certificate, QuickConnect certificate, and certificates from public CAs such as Let’s Encrypt, SSL.com, and Sectigo are not supported for this purpose. For ordinary home NAS owners, this may be irrelevant. For businesses using external key management, it belongs near the top of the pre-update checklist.

Don’t Assume Every Problem After an Update Was Caused by the Update

Timing can be misleading.
A hard drive can begin failing after a DSM update without the DSM update causing the failure.
A network cable can fail.
A UPS battery can deteriorate.
A container image can change.
A third-party application can have its own update.

Before blaming DSM, establish:

What worked before?
What exact version changed?
When did the problem begin?
Can it be reproduced?
Does Synology list it as a known or fixed issue?
Are other users reporting the same behavior?

That process separates repeatable DSM problems from coincidental hardware or application failures.

What Are Users Doing When 7.4.1 Works Normally?

It is worth emphasizing that community feedback is naturally biased toward problems. People whose NAS updated, rebooted, and continued working rarely create a long forum thread saying so. There are community reports of DSM 7.4.1 being installed successfully on multiple DiskStation systems without obvious issues. That is important context. A troubleshooting roundup should not create the impression that DSM 7.4.1 is universally unstable.

Instead, it highlights the configurations that deserve extra validation.

Use a Post-Update Acceptance Checklist

After installing DSM 7.4.1, don’t stop when the login screen returns.

Spend a few minutes validating the system.

Check:

Storage: Are all pools, volumes, HDDs, SSDs, and caches healthy?

Packages: Are required applications running and updated?

Backup: Did Hyper Backup, Active Backup, or other jobs resume?

Snapshots: Are new snapshots and replication jobs running?

UPS: Is the USB UPS detected and is the shutdown policy intact?

Network: Are SMB, NFS, VPN, remote access, and other required services reachable?

Containers/VMs: Did workloads restart correctly?

Notifications: Can the NAS still deliver alerts?

Logs: Are there new warnings that did not exist before the upgrade?

For a business NAS, record the results.

That turns an update from “DSM installed successfully” into an actual operational acceptance test.

When Should You Wait Before Installing a DSM Update?

Not every administrator needs to install a DSM release on launch day.

If your NAS is business-critical, heavily customized, dependent on third-party packages, or attached to unusual USB hardware, waiting for early field experience can be prudent. Security updates are different. A release fixing a vulnerability relevant to your environment may justify faster deployment.

The right strategy is therefore not:

Always update immediately

or:

Never install new DSM releases early.

Instead, evaluate security urgency against operational risk.

For businesses with multiple Synology systems, a staged deployment provides an excellent compromise:

Backup → test NAS → validate → secondary systems → production systems

DSM 7.4.1 Is Also a Reminder to Document Your Synology

Most difficult update problems become harder because nobody remembers exactly how the NAS was configured.

Before the next DSM update, maintain a basic inventory containing:

NAS model

DSM version

Drive models

Memory configuration

UPS model

Installed packages

Third-party packages

Containers and VMs

Backup destinations

Remote-access configuration

Critical scheduled tasks

If something changes after an update, you then have a baseline for comparison.

The Best Fix Is Often Verification, Not Random Changes

DSM 7.4.1-90080 officially corrects important problems introduced with DSM 7.4, particularly USB UPS and certain USB-device recognition issues. It also introduces compatibility considerations around Snapshot Replication and KMIP.

At the same time, community experiences show why administrators should still validate their individual hardware after updating. If you see an unverified drive, determine whether it is a compatibility warning or a failing disk. If your UPS disappears, confirm you’re actually running 7.4.1, check the physical connection and compatibility, and test the complete shutdown workflow.

If an application stops working, verify package compatibility before changing DSM itself. And if everything works, resist the temptation to start applying unofficial “fixes” for problems your system does not have.

About Epis Technology

Epis Technology helps businesses plan, test, and troubleshoot Synology DSM upgrades without unnecessarily disrupting storage and backup services. Services include DSM 7.4 migration and troubleshooting, drive compatibility assessments, HDD and SSD configuration, UPS integration, package compatibility reviews, Snapshot Replication, Hyper Backup, Active Backup for Business, Synology Drive, Container Manager, virtualization, ransomware resilience, and disaster recovery. Epis Technology can also develop staged Synology upgrade procedures and post-update acceptance checklists for organizations managing multiple NAS systems.