Support intro
Sorry to hear you’re facing problems. 
The community help forum (help.nextcloud.com) is for home and non-enterprise users. Support is provided by other community members on a best effort / “as available” basis. All of those responding are volunteering their time to help you.
If you’re using Nextcloud in a business/critical setting, paid and SLA-based support services can be accessed via portal.nextcloud.com where Nextcloud engineers can help ensure your business keeps running smoothly.
Getting help
In order to help you as efficiently (and quickly!) as possible, please fill in as much of the below requested information as you can.
Before clicking submit: Please check if your query is already addressed via the following resources:
- Official documentation (searchable and regularly updated)
- How to topics and FAQs
- Forum search
(Utilizing these existing resources is typically faster. It also helps reduce the load on our generous volunteers while elevating the signal to noise ratio of the forums otherwise arising from the same queries being posted repeatedly).
Some or all of the below information will be requested if it isn’t supplied; for fastest response please provide as much as you can. 
The Basics
- Nextcloud Server version (e.g., 29.x.x):
30.0.8
- Operating system and version (e.g., Ubuntu 24.04):
iOS 18.5
- Web server and version (e.g, Apache 2.4.25):
replace me
- Reverse proxy and version _(e.g. nginx 1.27.2)
replace me
- PHP version (e.g, 8.3):
replace me
- Is this the first time you’ve seen this error? (Yes / No):
Yes
- When did this problem seem to first start?
replace me
- Installation method (e.g. AlO, NCP, Bare Metal/Archive, etc.)
App Store
- Are you using CloudfIare, mod_security, or similar? (Yes / No)
No
Summary of the issue you are facing:
[…]
Steps to replicate it (hint: details matter!):
I attempted to backup all photos in iOS (iPhone) photos album. Many red errors at top of screen.
Completed transfer but having checked the totals on my phone and the totals transferred, some 400+ images missing.
What I would like to do is ensure all the missing photos are uploaded. I am reluctant to start the process again as I don’t want duplicates. I would like to know if the app will ask me what to do if it finds duplicates, and allow me to skip duplicated files.
If this is not the case does anyone have any suggestions on what I can about the errors I received please. Thank you
Log entries
Nextcloud
Please provide the log entries from your Nextcloud log that are generated during the time of problem (via the Copy raw option from Administration settings->Logging screen or from your nextcloud.log located in your data directory). Feel free to use a pastebin/gist service if necessary.
PASTE HERE
2025-07-12 07:57:59 [INFO] Network response request: https://de.tab.digital/index.php/core/preview?fileId=&x=1024&y=1024&a=1&mode=cover&forceIcon=0&mimeFallback=0, result: failure(Alamofire.AFError.responseValidationFailed(reason: Alamofire.AFError.ResponseValidationFailureReason.unacceptableStatusCode(code: 404)))
2025-07-12 07:57:59 [INFO] Network response request: https://de.tab.digital/index.php/core/preview?fileId=&x=1024&y=1024&a=1&mode=cover&forceIcon=0&mimeFallback=0, result: failure(Alamofire.AFError.responseValidationFailed(reason: Alamofire.AFError.ResponseValidationFailureReason.unacceptableStatusCode(code: 404)))
2025-07-12 07:57:59 [INFO] Network response request: https://de.tab.digital/index.php/core/preview?fileId=&x=1024&y=1024&a=1&mode=cover&forceIcon=0&mimeFallback=0, result: failure(Alamofire.AFError.responseValidationFailed(reason: Alamofire.AFError.ResponseValidationFailureReason.unacceptableStatusCode(code: 404)))
2025-07-12 07:58:00 [DEBUG] PROCESS (UPLOAD) find 1 items
2025-07-12 07:58:00 [DEBUG] Upload file 16-09-19 12-13-43 0131.jpg with Identifier 61F745EE-1667-4325-BCFB-8F6E95B5D74A/L0/001 with size 71336 [CHUNK 0, E2EE false]
#### Web Browser
If the problem is related to the Web interface, open your browser inspector *Console* and *Network* tabs while refreshing (reloading) and reproducing the problem. Provide any relevant output/errors here that appear.
PASTE
#### Web server / Reverse Proxy
The output of your Apache/nginx/system log in `/var/log/____`:
PASTE HERE
### Configuration
#### Nextcloud
The output of `occ config:list system` or similar is best, but, if not possible, the contents of your `config.php` file from `/path/to/nextcloud` is fine (make sure to remove any identifiable information!):
PASTE HERE
#### Apps
The output of `occ app:list` (if possible).
### Tips for increasing the likelihood of a response
* Use the `preformatted text` formatting option in the editor for all log entries and configuration output.
* If screenshots are useful, feel free to include them.
- If possible, also include key error output in text form so it can be searched for.
* Try to edit log output only minimally (if at all) so that it can be ran through analyzers / formatters by those trying to help you.