Android Client Sync failing - Unknown Error

[djxx]

For the last few weeks I've noticed my sync isn't working properly. On the server I don't see any errors, just lots of calls in the logs. On the client, it will cycle through trying to upload all the pending items, and the majority of them will fail and get put back into the queue to retry. In the majority of the files (>90%) the file has actually synced properly, but the client doesn't think so and tries again. I'm worried some files will get missed if I ignore this issue.

Feb 08 13:48:20 IP_ADDRESS - USER [08/Feb/2026:21:48:17 +0000] "GET /index.php/core/preview?fileId=1240097&x=256&y=256&a=1&mode=cover&forceIcon=0 HTTP/1.1" 200 137849 "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:20 IP_ADDRESS - USER [08/Feb/2026:21:48:17 +0000] "PUT /remote.php/dav/files/USER/InstantUpload/Screenshots/2025/06/Screenshot_20250620-023950.png HTTP/1.1" 201 - "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:20 IP_ADDRESS - USER [08/Feb/2026:21:48:20 +0000] "HEAD /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260205_001058649.jpg HTTP/1.1" 200 - "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:20 IP_ADDRESS - USER [08/Feb/2026:21:48:20 +0000] "HEAD /remote.php/dav/files/USER/InstantUpload/Screenshots/2025/06/Screenshot_20250620-024042.png HTTP/1.1" 404 - "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:20 IP_ADDRESS - USER [08/Feb/2026:21:48:20 +0000] "PROPFIND /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260205_001058649.jpg HTTP/1.1" 207 1646 "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:20 IP_ADDRESS - USER [08/Feb/2026:21:48:20 +0000] "PROPFIND /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260205_001103777.jpg HTTP/1.1" 207 1646 "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:20 IP_ADDRESS - USER [08/Feb/2026:21:48:20 +0000] "PROPFIND /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260205_001103777.jpg HTTP/1.1" 207 1646 "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:20 IP_ADDRESS - USER [08/Feb/2026:21:48:20 +0000] "PROPFIND /remote.php/dav/files/USER/InstantUpload/Screenshots/2025/06/Screenshot_20250620-023950.png HTTP/1.1" 207 1533 "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:21 IP_ADDRESS - USER [08/Feb/2026:21:48:20 +0000] "PROPFIND /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260205_001058649.jpg HTTP/1.1" 207 1646 "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:21 IP_ADDRESS - USER [08/Feb/2026:21:48:21 +0000] "HEAD /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260205_001046902.jpg HTTP/1.1" 200 - "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:21 IP_ADDRESS - USER [08/Feb/2026:21:48:21 +0000] "HEAD /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260205_001102555.jpg HTTP/1.1" 200 - "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:21 IP_ADDRESS - USER [08/Feb/2026:21:48:21 +0000] "PROPFIND /remote.php/dav/files/USER/ HTTP/1.1" 207 2364 "-" "Mozilla/5.0 (Linux) mirall/4.0.1 (build 34593) (Nextcloud, linuxmint-6.17.0-14-generic ClientArchitecture: x86_64 OsArchitecture: x86_64)"
Feb 08 13:48:21 IP_ADDRESS - USER [08/Feb/2026:21:48:21 +0000] "PROPFIND /remote.php/dav/files/USER/InstantUpload HTTP/1.1" 207 1119 "-" "Mozilla/5.0 (Linux) mirall/4.0.1 (build 34593) (Nextcloud, linuxmint-6.17.0-14-generic ClientArchitecture: x86_64 OsArchitecture: x86_64)"
Feb 08 13:48:21 IP_ADDRESS - USER [08/Feb/2026:21:48:21 +0000] "PROPFIND /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260205_001102555.jpg HTTP/1.1" 207 1646 "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:21 IP_ADDRESS - USER [08/Feb/2026:21:48:21 +0000] "PROPFIND /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260205_001102555.jpg HTTP/1.1" 207 1646 "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:22 IP_ADDRESS - USER [08/Feb/2026:21:48:21 +0000] "PROPFIND /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260205_001046902.jpg HTTP/1.1" 207 1646 "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:22 IP_ADDRESS - USER [08/Feb/2026:21:48:22 +0000] "GET /remote.php/dav/files/USER/InstantUpload/Screenshots/2025/06/Screenshot_20250620-023950.png HTTP/1.1" 200 994782 "-" "Mozilla/5.0 (Linux) mirall/4.0.1 (build 34593) (Nextcloud, linuxmint-6.17.0-14-generic ClientArchitecture: x86_64 OsArchitecture: x86_64)"
Feb 08 13:48:22 IP_ADDRESS - USER [08/Feb/2026:21:48:22 +0000] "GET /remote.php/dav/files/USER/InstantUpload/Screenshots/2025/06/Screenshot_20250620-024042.png HTTP/1.1" 200 1111383 "-" "Mozilla/5.0 (Linux) mirall/4.0.1 (build 34593) (Nextcloud, linuxmint-6.17.0-14-generic ClientArchitecture: x86_64 OsArchitecture: x86_64)"
Feb 08 13:48:22 IP_ADDRESS - USER [08/Feb/2026:21:48:22 +0000] "HEAD /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260204_200634502.jpg HTTP/1.1" 200 - "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:22 IP_ADDRESS - USER [08/Feb/2026:21:48:22 +0000] "PROPFIND /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260204_200634502.jpg HTTP/1.1" 207 1646 "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:22 IP_ADDRESS - USER [08/Feb/2026:21:48:22 +0000] "PROPFIND /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260204_200634502.jpg HTTP/1.1" 207 1646 "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:22 IP_ADDRESS - USER [08/Feb/2026:21:48:22 +0000] "PROPFIND /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260205_001046902.jpg HTTP/1.1" 207 1646 "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:22 IP_ADDRESS - USER [08/Feb/2026:21:48:22 +0000] "PROPFIND /remote.php/dav/files/USER/InstantUpload/Screenshots HTTP/1.1" 207 760 "-" "Mozilla/5.0 (Linux) mirall/4.0.1 (build 34593) (Nextcloud, linuxmint-6.17.0-14-generic ClientArchitecture: x86_64 OsArchitecture: x86_64)"
Feb 08 13:48:22 IP_ADDRESS - USER [08/Feb/2026:21:48:22 +0000] "PROPFIND /remote.php/dav/files/USER/InstantUpload/Screenshots/2025 HTTP/1.1" 207 827 "-" "Mozilla/5.0 (Linux) mirall/4.0.1 (build 34593) (Nextcloud, linuxmint-6.17.0-14-generic ClientArchitecture: x86_64 OsArchitecture: x86_64)"
Feb 08 13:48:22 IP_ADDRESS - USER [08/Feb/2026:21:48:22 +0000] "PROPFIND /remote.php/dav/files/USER/InstantUpload/Screenshots/2025/06 HTTP/1.1" 207 2409 "-" "Mozilla/5.0 (Linux) mirall/4.0.1 (build 34593) (Nextcloud, linuxmint-6.17.0-14-generic ClientArchitecture: x86_64 OsArchitecture: x86_64)"
Feb 08 13:48:23 IP_ADDRESS - USER [08/Feb/2026:21:48:20 +0000] "GET /index.php/core/preview?fileId=1240105&x=256&y=256&a=1&mode=cover&forceIcon=0 HTTP/1.1" 200 127416 "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:23 IP_ADDRESS - USER [08/Feb/2026:21:48:23 +0000] "HEAD /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260206_030342845.jpg HTTP/1.1" 200 - "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:23 IP_ADDRESS - USER [08/Feb/2026:21:48:23 +0000] "HEAD /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260206_041450379.jpg HTTP/1.1" 200 - "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:23 IP_ADDRESS - USER [08/Feb/2026:21:48:23 +0000] "PROPFIND /remote.php/dav/files/USER/ HTTP/1.1" 207 236 "-" "Mozilla/5.0 (Linux) mirall/4.0.1 (build 34593) (Nextcloud, linuxmint-6.17.0-14-generic ClientArchitecture: x86_64 OsArchitecture: x86_64)"
Feb 08 13:48:23 IP_ADDRESS - USER [08/Feb/2026:21:48:23 +0000] "PROPFIND /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260206_030342845.jpg HTTP/1.1" 207 1646 "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"
Feb 08 13:48:23 IP_ADDRESS - USER [08/Feb/2026:21:48:23 +0000] "PROPFIND /remote.php/dav/files/USER/InstantUpload/2026/02/Camera/PXL_20260206_030342845.jpg HTTP/1.1" 207 1646 "-" "Mozilla/5.0 (Android) Nextcloud-android/3.35.2"

[james]

Hello @djxx

Do the failing files on android have something in common?
For example, I know that when deleting pictures on a Google Pixel phone they get moved into a paperbin / trash location on the phone.
I have seen this behaviour cause some confusion for the Nextcloud Client when the client has already qued the picture to be uploaded.
Maybe the same can occour when moving picutres to specific folders on android when the upload is already qued from the original location?
This is just speculation.

But please check if the failing files have something in common.