Product attachments will not download and show as failed download

### WordPress Environment ###

WordPress address (URL): https://systemsenvironmental.com
Site address (URL): https://systemsenvironmental.com
WC Version: 4.9.1
REST API Version: ? 4.9.1
WC Blocks Version: ? 4.0.0
Action Scheduler Version: ? 3.1.6
WC Admin Version: ? 1.8.3
Log Directory Writable: ?
WP Version: 5.6
WP Multisite: –
WP Memory Limit: 2 GB
WP Debug Mode: –
WP Cron: –
Language: en_US
External object cache: –

### Server Environment ###

Server Info: Apache
PHP Version: 7.3.25
PHP Post Max Size: 2 GB
PHP Time Limit: 300
PHP Max Input Vars: 16384
cURL Version: 7.29.0
NSS/3.53.1

SUHOSIN Installed: –
MySQL Version: 5.5.5-10.2.35-MariaDB
Max Upload Size: 2 GB
Default Timezone is UTC: ?
fsockopen/cURL: ?
SoapClient: ?
DOMDocument: ?
GZip: ?
Multibyte String: ?
Remote Post: ?
Remote Get: ?

### Database ###

WC Database Version: 4.9.1
WC Database Prefix: wp_
Total Database Size: 59.53MB
Database Data Size: 47.45MB
Database Index Size: 12.08MB
wp_woocommerce_sessions: Data: 7.02MB + Index: 0.16MB + Engine InnoDB
wp_woocommerce_api_keys: Data: 0.02MB + Index: 0.03MB + Engine InnoDB
wp_woocommerce_attribute_taxonomies: Data: 0.02MB + Index: 0.02MB + Engine InnoDB
wp_woocommerce_downloadable_product_permissions: Data: 0.02MB + Index: 0.06MB + Engine InnoDB
wp_woocommerce_order_items: Data: 0.02MB + Index: 0.02MB + Engine InnoDB
wp_woocommerce_order_itemmeta: Data: 0.14MB + Index: 0.14MB + Engine InnoDB
wp_woocommerce_tax_rates: Data: 0.02MB + Index: 0.06MB + Engine InnoDB
wp_woocommerce_tax_rate_locations: Data: 0.02MB + Index: 0.03MB + Engine InnoDB
wp_woocommerce_shipping_zones: Data: 0.02MB + Index: 0.00MB + Engine InnoDB
wp_woocommerce_shipping_zone_locations: Data: 0.02MB + Index: 0.03MB + Engine InnoDB
wp_woocommerce_shipping_zone_methods: Data: 0.02MB + Index: 0.00MB + Engine InnoDB
wp_woocommerce_payment_tokens: Data: 0.02MB + Index: 0.02MB + Engine InnoDB
wp_woocommerce_payment_tokenmeta: Data: 0.02MB + Index: 0.03MB + Engine InnoDB
wp_woocommerce_log: Data: 0.02MB + Index: 0.02MB + Engine InnoDB
wp_actionscheduler_actions: Data: 2.02MB + Index: 0.48MB + Engine InnoDB
wp_actionscheduler_claims: Data: 0.02MB + Index: 0.02MB + Engine InnoDB
wp_actionscheduler_groups: Data: 0.02MB + Index: 0.02MB + Engine InnoDB
wp_actionscheduler_logs: Data: 0.38MB + Index: 0.30MB + Engine InnoDB
wp_commentmeta: Data: 0.02MB + Index: 0.03MB + Engine InnoDB
wp_comments: Data: 0.11MB + Index: 0.09MB + Engine InnoDB
wp_failed_jobs: Data: 0.00MB + Index: 0.00MB + Engine MyISAM
wp_links: Data: 0.02MB + Index: 0.02MB + Engine InnoDB
wp_mailchimp_carts: Data: 0.01MB + Index: 0.00MB + Engine MyISAM
wp_mailchimp_jobs: Data: 0.00MB + Index: 0.00MB + Engine MyISAM
wp_options: Data: 4.50MB + Index: 0.17MB + Engine InnoDB
wp_postmeta: Data: 20.55MB + Index: 7.00MB + Engine InnoDB
wp_posts: Data: 6.52MB + Index: 0.70MB + Engine InnoDB
wp_queue: Data: 0.00MB + Index: 0.00MB + Engine MyISAM
wp_redirection_404: Data: 0.02MB + Index: 0.05MB + Engine InnoDB
wp_redirection_groups: Data: 0.02MB + Index: 0.03MB + Engine InnoDB
wp_redirection_items: Data: 0.02MB + Index: 0.09MB + Engine InnoDB
wp_redirection_logs: Data: 0.02MB + Index: 0.05MB + Engine InnoDB
wp_revslider_css: Data: 0.13MB + Index: 0.00MB + Engine InnoDB
wp_revslider_layer_animations: Data: 0.02MB + Index: 0.00MB + Engine InnoDB
wp_revslider_navigations: Data: 0.02MB + Index: 0.00MB + Engine InnoDB
wp_revslider_sliders: Data: 0.06MB + Index: 0.00MB + Engine InnoDB
wp_revslider_slides: Data: 0.28MB + Index: 0.00MB + Engine InnoDB
wp_revslider_static_slides: Data: 0.02MB + Index: 0.00MB + Engine InnoDB
wp_smush_dir_images: Data: 0.02MB + Index: 0.03MB + Engine InnoDB
wp_termmeta: Data: 0.05MB + Index: 0.03MB + Engine InnoDB
wp_terms: Data: 0.02MB + Index: 0.03MB + Engine InnoDB
wp_term_relationships: Data: 0.13MB + Index: 0.09MB + Engine InnoDB
wp_term_taxonomy: Data: 0.06MB + Index: 0.03MB + Engine InnoDB
wp_usermeta: Data: 0.25MB + Index: 0.19MB + Engine InnoDB
wp_users: Data: 0.02MB + Index: 0.05MB + Engine InnoDB
wp_wc_admin_notes: Data: 0.02MB + Index: 0.00MB + Engine InnoDB
wp_wc_admin_note_actions: Data: 0.02MB + Index: 0.02MB + Engine InnoDB
wp_wc_category_lookup: Data: 0.02MB + Index: 0.00MB + Engine InnoDB
wp_wc_customer_lookup: Data: 0.02MB + Index: 0.03MB + Engine InnoDB
wp_wc_download_log: Data: 0.02MB + Index: 0.03MB + Engine InnoDB
wp_wc_order_coupon_lookup: Data: 0.02MB + Index: 0.03MB + Engine InnoDB
wp_wc_order_product_lookup: Data: 0.02MB + Index: 0.06MB + Engine InnoDB
wp_wc_order_stats: Data: 0.02MB + Index: 0.05MB + Engine InnoDB
wp_wc_order_tax_lookup: Data: 0.02MB + Index: 0.03MB + Engine InnoDB
wp_wc_product_meta_lookup: Data: 0.13MB + Index: 0.17MB + Engine InnoDB
wp_wc_reserved_stock: Data: 0.02MB + Index: 0.00MB + Engine InnoDB
wp_wc_tax_rate_classes: Data: 0.00MB + Index: 0.01MB + Engine MyISAM
wp_wc_webhooks: Data: 0.02MB + Index: 0.02MB + Engine InnoDB
wp_woocommerce_per_product_shipping_rules: Data: 0.20MB + Index: 0.00MB + Engine InnoDB
wp_woocommerce_shipping_table_rates: Data: 0.02MB + Index: 0.00MB + Engine InnoDB
wp_yith_wapo_groups: Data: 0.02MB + Index: 0.00MB + Engine InnoDB
wp_yith_wapo_types: Data: 0.02MB + Index: 0.00MB + Engine InnoDB
wp_yith_wccl_meta: Data: 0.02MB + Index: 0.00MB + Engine InnoDB
wp_yith_wcwl: Data: 0.09MB + Index: 0.02MB + Engine InnoDB
wp_yith_wcwl_lists: Data: 0.13MB + Index: 0.11MB + Engine InnoDB
wp_yoast_indexable: Data: 3.52MB + Index: 1.11MB + Engine InnoDB
wp_yoast_indexable_hierarchy: Data: 0.06MB + Index: 0.08MB + Engine InnoDB
wp_yoast_migrations: Data: 0.02MB + Index: 0.02MB + Engine InnoDB
wp_yoast_primary_term: Data: 0.02MB + Index: 0.03MB + Engine InnoDB
wp_yoast_seo_links: Data: 0.20MB + Index: 0.14MB + Engine InnoDB
wp_yoast_seo_meta: Data: 0.05MB + Index: 0.00MB + Engine InnoDB

### Post Type Counts ###

attachment: 2503
ct_template: 7
custom_css: 2
mc4wp-form: 1
nav_menu_item: 154
oembed_cache: 12
page: 25
post: 6
postman_sent_mail: 250
product: 908
revision: 567
shop_coupon: 1
shop_order: 54
static_block: 6
wc_conditional_fee: 1
wpcf7_contact_form: 5

### Security ###

Secure connection (HTTPS): ?
Hide errors from visitors: ?

### Active Plugins (24) ###

Redux: by Redux.io + Dovy Paukstys – 4.1.24
Add From Server: by Dion Hulse – 3.4.5
Adminimize: by Frank Bültge – 1.11.7
Cache Enabler: by KeyCDN – 1.6.2
Contact Form 7: by Takayuki Miyoshi – 5.3.2
Electro Extensions: by MadrasThemes – 2.3.3 – Installed version not tested with active version of WooCommerce 4.0
Enable jQuery Migrate Helper: by The WordPress Team – 1.3.0
Flexible Shipping UPS: by WP Desk – 1.11.0
WPBakery Page Builder: by Michael M - WPBakery.com – 6.0.3
Mailchimp for WooCommerce: by Mailchimp – 2.5.0
MC4WP: Mailchimp for WordPress: by ibericode – 4.8.3
Post SMTP: by Yehuda Hassine – 2.0.19
Slider Revolution: by ThemePunch – 5.4.8.3
Search By SKU - for Woocommerce: by Unroll Digital – 0.7.1
Shipper Pro: by WPMU DEV – 1.2.4
Sucuri Security - Auditing, Malware Scanner and Hardening: by Sucuri Inc. – 1.8.25
WooCommerce Product Attachment: by theDotstore – 1.7
WooCommerce Stripe Gateway: by WooCommerce – 4.7.0
WooCommerce Price Based on Country (Basic): by Oscar Gare – 2.0.14
WooCommerce: by Automattic – 4.9.1 (update to version 4.9.2 is available)
Yoast SEO: by Team Yoast – 15.6.2
WP Force SSL: by WebFactory Ltd – 1.56
WPMU DEV Dashboard: by WPMU DEV – 4.10.6
YITH WooCommerce Wishlist: by YITH – 3.0.18

### Inactive Plugins (9) ###

Automated FedEx Shipping: by HITShipo – 2.5.13
CDN Enabler: by KeyCDN – 1.0.9
Disable Comments: by WPDeveloper – 2.0.2
Disable Real MIME Check: by Sergey Biryukov – 1.0
FedEx WooCommerce Extension (BASIC): by PluginHive – 2.1.5 – Installed version not tested with active version of WooCommerce 4.0
Flexible Shipping For FedEx: by WP Desk – 1.5.3
Regenerate Thumbnails: by Alex Mills (Viper007Bond) – 3.1.4
Thumbnail Cleaner: by Kolja Nolte – 1.4.2
WooCommerce Price Based on Country Pro Add-on: by Oscar Gare – 2.8.7

### Dropin Plugins (2) ###

advanced-cache.php: advanced-cache.php
fatal-error-handler.php: fatal-error-handler.php

### Must Use Plugins (2) ###

Disable Environment Indicator: by Nexcess – 1.0
Nexcess Managed Apps: by Nexcess – 1.15.1

### Settings ###

API Enabled: ?
Force SSL: –
Currency: CAD ($)
Currency Position: left
Thousand Separator: ,
Decimal Separator: .
Number of Decimals: 2
Taxonomies: Product Types: external (external)
grouped (grouped)
simple (simple)
variable (variable)

Taxonomies: Product Visibility: exclude-from-catalog (exclude-from-catalog)
exclude-from-search (exclude-from-search)
featured (featured)
outofstock (outofstock)
rated-1 (rated-1)
rated-2 (rated-2)
rated-3 (rated-3)
rated-4 (rated-4)
rated-5 (rated-5)

Connected to WooCommerce.com: ?

### WC Pages ###

Shop base: #3853 - /shop/
Cart: #3134 - /cart/
Checkout: #3135 - /checkout/
My account: #3854 - /my-account/
Terms and conditions: #2183 - /terms-and-conditions/

### Theme ###

Name: Electro Child
Version: 2.3.3
Author URL: https://madrasthemes.com/
Child Theme: ?
Parent Theme Name: Electro
Parent Theme Version: 2.7.1
Parent Theme Author URL: https://madrasthemes.com/
WooCommerce Support: ?

### Templates ###

Overrides: electro/woocommerce/archive-product.php
electro-child/woocommerce/emails/customer-invoice.php
electro/woocommerce/global/quantity-input.php

### Geolocation debug info ###

Default customer location: geolocation
MaxMind GeoIP database: ?
MaxMind GeoIP license: ?
MM_COUNTRY_CODE: ?
GEOIP_COUNTRY_CODE: US
HTTP_CF_IPCOUNTRY: ?
HTTP_X_COUNTRY_CODE: ?
HTTP_X_REAL_IP: ?
HTTP_X_FORWARDED_FOR: 67.2.63.229
REMOTE_ADDR: 67.2.63.229
Real external IP: 67.2.63.229
WCPBC_USE_REMOTE_ADDR: –
Geolocation Test: ?

### PBC Settings ###

Version: 2.0.14
Base location: CA:ON
Base currency: CAD
Price Based On: shipping
Shipping: –
Test mode: –
Test country: –
Load products price in background: –
Prices entered with tax: –
Calculate tax based on: shipping
Display prices in the shop: excl

### Zone Pricing Canada ###

zone_id: canada
name: Canada
countries: CA
currency: CAD
exchange_rate: 1
auto_exchange_rate: yes
disable_tax_adjustment: no
exchange_rate_fee: 0
round_nearest: 
currency_format: [symbol][price] CAD
price_thousand_sep: ,
price_decimal_sep: .
price_num_decimals: 2

### Zone Pricing United States ###

zone_id: united-states
name: United States
countries: US
currency: USD
exchange_rate: 0.785087
auto_exchange_rate: yes
disable_tax_adjustment: no
exchange_rate_fee: 0
round_nearest: 
currency_format: [symbol][price] USD
price_thousand_sep: ,
price_decimal_sep: .
price_num_decimals: 2

### Action Scheduler ###

Complete: 1,659
Oldest: 2020-12-27 21:20:39 +0000
Newest: 2021-01-27 20:00:08 +0000

Pending: 2
Oldest: 2021-01-27 21:00:08 +0000
Newest: 2021-01-27 21:00:08 +0000

Hello there,

Thanks for contacting us.

I have reviewed your query that you are getting some issues while downloading the attachment files.

This is your site specific issue due to theme conflict or other plugin conflict or might due to attachment permission issue.

Can you please try the below mentioned step to check if there is any issue related to the permission or blocking by browser or not?

Click here to review the link to follow the steps.

Please also make sure that uploaded attachments have full permission to download.

Best Regards,
Hitendra & Dotstore team

Hello, I am working on this issue as well. I have been able to replicate the website in a different environment, and the download functions properly without the need to disable the theme or plugins. You can see it in action at:
https://dev.thinkrmedia.com/systems/product/100-gallon-pco-poly-tank/

I have tried going the route of disabling theme and plugins to troubleshoot, in the staging environment provided for the original website. It’s available at
https://3f9027e66e.nxcli.net/product/seaflo-diaphragm-pump-5-0-gpm-60-psi-4/

Is there still a possibility it could be a theme/plugin conflict? It works fine with everything active at the first URL I posted, but with only the bare minimum activated on the second URL, it doesn’t work.

I’ve also tested this in Edge and Firefox with identical results.

Looks like the issue is related to.

Correctly close all nested output buffers before writing the file.

while (ob_get_level() > 0) { ob_end_clean(); }

• This reply was modified 3 years, 9 months ago by Luke Cavanagh. Reason: clarify wording

To expand on the above, the exact issue we have been seeing is related to KeyCDN’s cache-enabler plugin combined with any other plugin/theme that opens an output buffer (ob_start). In this situation cache-enabler creates a nested output buffer (ob_get_level() >= 2), with the cache-enabler output buffer using a callback.

While woo-product-attachments does call ob_flush while writing the file to the browser, this would only write to the browser if ob_get_level == 1. If there are two output buffers open the plugin may still work — but if one of the output buffers has a callback defined (eg, cache-enabler), then the ob_flush would only write to cache-enabler’s output buffer. At that point it’s up to the callback in the other plugin to determine if/how/when to write the file to the browser.

I believe a decent solution to solve this would be to close all output buffers prior to writing the file. eg, add this line above the headers() calls in woo-product-attachment/public/class-woocommerce-product-attachment-public.php:

while (ob_get_level() > 0) { ob_end_clean(); }

At the very least this resolves the compatibility issues with cache-enabler.

— alexis

Hello there,

Thank you for providing the details about the issue which is coming with appropriate solutions.

We will review and apply all above ways of solution and implement best which will work for us.

Thank you,
Hitendra & Dotstore Team