Unable to add attachments to feature services hosted in ArcGIS Enterprise

Description

When attempting to add attachments to a feature service in a web map, only files less than 100 KB can be added. Attachments above 100 KB cannot be attached without returning error messages.

The DEBUG level ArcGIS Server logs returns the error message below after attempts to add an attachment over 100 KB in the Portal for ArcGIS web map fail.

Error:
Unable to process request. Error parsing multi-part request.

Following attempts to add the attachments in ArcGIS Collector, another error message is returned.

Error:
Attachment failed to upload

Attempts to add the attachments to the feature service in ArcGIS Pro also fail and the error message below is returned.

Error:
Edit operation failed. Internal Server error. (Status code 500).

Cause

• A value lower than the size of the attachment is set in the uploadReadAheadSize property in Internet Information Services (IIS) Manager. Refer to Microsoft: UploadReadAheadSize for more information.
• There is insufficient disk space on the drive hosting the ArcGIS Server site.

Solution or Workaround

Increase the uploadReadAheadSize property value in Internet Information Services (IIS) Manager

1. On the hosting machine, open Internet Information Services (IIS) Manager.
2. In the Connections pane, select the site hosting the web application.
3. On the Features View tab, double-click Configuration Editor under Management.

4. In the Section drop-down menu, expand system.webServer and select serverRuntime.
5. Increase the uploadReadAheadSize value. In this example, the value is increased to 20000000 bytes (20 MB).
6. Under Actions, click Apply .

Increase the disk space of the ArcGIS Server site machine

The following measures can be taken to increase the disk space on the ArcGIS Server site machine:

• Increase the disk space to at least 20 GB. If the space drops below 10 GB, a low disk warning is logged in the ArcGIS Server logs. Refer to ArcGIS Server: Disk space monitoring in ArcGIS Server for more information.
• Delete some of the old logs if the size of the logs folder is large (in GB). Refer to Problem: The volume of ArcGIS Server logs affects performance for instructions.

Add attachments using the ArcGIS Server REST services

An alternative is to upload attachments using the ArcGIS Server REST services. Refer to How To: Add large attachments to a feature using the ArcGIS REST Services Directory for more instructions and information.