[Bug]: Files larger than 100 MB fail to upload in directories with special characters in their names (e.g., SQ-0.5%BF-150).

[zhangjm365]

⚠️ This issue respects the following points: ⚠️

• This is a bug, not a question or a configuration/webserver/proxy issue.
• This issue is not already reported on Github OR Nextcloud Community Forum (I've searched it).
• Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
• I agree to follow Nextcloud's Code of Conduct.

Bug description

Nextcloud server version: 32.0.3
Nextcloud client version: 4.0.4
When a directory name contains a specific string—such as SQ-0.5%BF-150—and the directory contains relatively large files, synchronization fails with the error message:
"Path error: File/folder does not exist."
In this directory, I tested uploading a 120 MB file, which failed, while a 98 MB file uploaded successfully. This suggests the failure threshold may be around 100 MB.
The issue is 100% reproducible and occurs in both the Snap and AIO (All-in-One) versions.
NEXTCLOUD版本32.0.3，客户端版本4.0.4 。
当目录名中带有特定字符串，比如SQ-0.5%BF-150，并且该目录下文件大于130MB时，同步会失败，报的错误信息为
路径错误，文件/文件夹不存在，我测试了98MB大小的文件，在同一目录下上传是成功，猜测临界值可能是100MB，
复现率100%，在SNAP版本和AIO版本均可复现。

Steps to reproduce

1.Create a synced folder.
2.Inside the synced folder, create a directory named SQ-0.5%BF-150.
3.Place a file larger than 120 MB into this directory.

Expected behavior

The file uploads and syncs successfully without any errors.Actual behavior:
Sync fails with the error: "Path error: File/folder does not exist."

Nextcloud Server version

32

Operating system

Debian/Ubuntu

PHP engine version

None

Web server

None

Database engine version

None

Is this bug present after an update or on a fresh install?

None

Are you using the Nextcloud Server Encryption module?

None

What user-backends are you using?

• Default user-backend (database)
• LDAP/ Active Directory
• SSO - SAML
• Other

Configuration report

List of activated Apps

Nextcloud Signing status

Nextcloud Logs

Additional info

No response

[come-nc]

Hello,

The 100MB threshold would indicate an issue with chunked uploads I suppose.
Do you have the same issue in the web UI or only with the desktop client?

[zhangjm365]

Only the sync folder function of the desktop client has this problem; uploading large files via the web interface works normally. My directory name is: "SQ-0.5%BF-150". When the desktop client reports an error, this segment of the path will be displayed as "SQ-0.5%25BF-150".

[zhangjm365]

Testing was conducted using the Nextcloud Desktop Client Daily Build 20260116, and the issue persists. The system functions normally if the characters following the % symbol in the directory name are not all hexadecimal letters (A-F). For example, everything works fine with a directory named "SQ-0.5%CM-150".

[joshtrichards]

On the surface, it sounds like a double decoding matter, but both the Web and Desktop client transactions utilize the same underlying server-side handling.

Looking closer, based on the provided error output, it looks like the client is properly encoding the % -> %25, but the non-ASCII elements of the path aren't being encoded. I presume the client doesn't decode those merely for the error message, so that points at a client URL encoding problem.

When did this behavior start for you? Did these paths work for you previously?