If your browser forces a download when you access a file in OSS, check your OSS, CDN, and browser settings.
Item to check | Cause | Solution |
OSS | When you use a default domain name or an acceleration endpoint to access certain types of files, such as files with a Content-Type of text/html or image/jpeg, in a bucket created after a specific time, OSS adds download headers ( | Use a custom domain name and attach it to the bucket. For more information, see Default domain names. |
The | Set an appropriate Content-Type. For more information, see How do I set the Content-Type (MIME)?. | |
The | Set Content-Disposition to | |
CDN | The resource has not been purged from the CDN cache. | Purge the resource from the CDN cache. For more information, see Refresh and prefetch resources. |
Browser | The browser does not support previewing this file format. | You can install a browser extension |
Appendix: x-oss-ec rules that trigger forced downloads
The following x-oss-ec rules trigger forced downloads when you use default domain names or acceleration endpoints to access certain types of files.
OSS default domain names
The following table describes the effective periods and other information for OSS default domain names in different regions.
Effective region | Effective period | Affected object | Content-Type | x-oss-ec |
China (Hangzhou), China (Shanghai), China (Qingdao), China (Beijing), China (Zhangjiakou), China (Hohhot), China (Shenzhen), China (Chengdu) | From 08:00 on September 28, 2018 | Buckets created in the specified region | text/html | |
China (Nanjing - Local Region - Decommissioning), China (Fuzhou - Local Region - Decommissioning), China (Wuhan - Local Region), China (Ulanqab), China (Heyuan), China (Guangzhou), US (Silicon Valley), US (Virginia), South Korea (Seoul), Singapore, Malaysia (Kuala Lumpur), Indonesia (Jakarta), Philippines (Manila), Thailand (Bangkok), UK (London), UAE (Dubai) | From 12:00 on September 25, 2019 | |||
China (Hong Kong) | From 14:00 on November 25, 2019 | |||
China (Hohhot) | From 17:00 on September 23, 2019 |
| ||
China (Qingdao), China (Chengdu) | From 11:00 on September 24, 2019 | |||
China (Zhangjiakou) | From 17:00 on September 24, 2019 | |||
China (Shanghai), China (Shenzhen) | From 17:00 on September 29, 2019 | |||
China (Beijing) | From 18:00 on September 29, 2019 | |||
China (Hangzhou) | From 15:00 on September 30, 2019 | |||
From 00:00 on October 09, 2022 | Users who have activated OSS |
Acceleration endpoints
The following table describes the effective periods and other information for acceleration endpoints in different regions.
Effective region | Effective period | Affected object | Content-Type | x-oss-ec |
From 00:00 on December 31, 2020 | Buckets for which transfer acceleration is enabled in the specified region | text/html | ||
UAE (Dubai) | From 12:00 on January 07, 2021 | |||
Malaysia (Kuala Lumpur), UK (London) | From 18:00 on January 07, 2021 | |||
Japan (Tokyo), Indonesia (Jakarta), Germany (Frankfurt) | From 18:00 on January 08, 2021 | |||
US (Silicon Valley), US (Virginia), Singapore | From 12:00 on January 14, 2021 | |||
China (Hong Kong) | From 00:00 on January 16, 2021 | |||
SAU (Riyadh - Partner Region), South Korea (Seoul), Philippines (Manila), Thailand (Bangkok) | From 00:00 on February 01, 2023 |