Troubleshooting & FAQs
Troubleshooting Common Issues
404 Redirect Error During OAuth
Problem: Merchant clicks the installation link and sees a 404 error from Shopify during the OAuth redirect.
Cause: The App URL in Shopify Partner Dashboard uses a different host than the Redirect URI. Shopify requires both URLs to share the same host.
What went wrong:
❌ App URL:
https://yourcompany.com+ Redirect URI:https://connect.violet.io/...→ Hosts don't match✅ App URL:
https://connect.violet.io/your-alias+ Redirect URI:https://connect.violet.io/your-alias/...→ Hosts match
Solution:
Go to Shopify Partner Dashboard → App Distribution
Navigate to your Custom App → select View on Dev Dashboard (far right link)
Click Configuration (or App setup)
Update the App URL field to:
Live Mode:
https://connect.violet.io/{YOUR_APP_ALIAS}Test Mode:
https://connect.violet.dev/{YOUR_APP_ALIAS}
Verify the Redirect URI uses the same host as the App URL
Save changes
Have the merchant retry the installation link
Finding Your App Alias: Channel Dashboard → App Settings → Violet Connect
Prevention: See Shopify App Setup for correct configuration.
Install Link Missing or Invalid
Problem: Cannot find the Install Link in Shopify Partner Dashboard, or the Install Link field shows an error in Violet pre-registration.
Cause: Custom distribution was not selected for the app.
Solution:
Go to Shopify Partner Dashboard → App Distribution → Your Custom App
Look for the Distribution section on the app overview page
Click "Select distribution method"
Choose "Custom distribution" and confirm
After selection, you'll see the Distribution page with the Install Link
Copy the Install Link and use it in your Violet pre-registration

Prevention: Always select "Custom distribution" immediately after creating your custom app. See Shopify App Setup - Step 5.
Merchant Clicked Violet Connect Before Installing App
Problem: Merchant clicked the Violet Connect link but sees an error because the app isn't installed.
Cause: The merchant needs to install the custom app via the Shopify Install Link BEFORE using Violet Connect.
Solution:
Ask the merchant to close the Violet Connect page
Send them the Shopify Install Link (Channel Dashboard → Pre-Registered → Actions → Copy Shopify Install Link)
Have them click the Install Link and complete app installation in Shopify admin
After installation is confirmed, send them the Violet Connect link again
They should now be able to complete onboarding successfully
Prevention: Always send the Shopify Install Link first and confirm the merchant has installed the app before sending the Violet Connect link.
Wrong Store URL
Problem: Merchant reports the Violet Connect link shows the wrong store name/URL.
Cause: Store URL was entered incorrectly during pre-registration.
Solution:
Delete the incorrect pre-registration (Actions menu → Delete)
Create a new pre-registration with the correct store URL
Copy and send the new Violet Connect link to merchant
Permission Errors - Features Don't Work
Problem: Merchant completes installation but features don't work (products missing, shipping rates not calculating, etc.)
Cause: Missing API scopes in the custom app configuration.
Solution:
Go to Shopify Partner Dashboard → App Distribution
Navigate to your Custom App → select View on Dev Dashboard (far right link)
Check Configuration tab → Admin API access scopes
Add missing scopes from Prerequisites section
Update pre-registration: Actions menu → Edit
Have merchant use new link and reinstall
Missing Credentials from Shopify Partner Dashboard
Problem: Can't pre-register merchant because you don't have credentials.
Cause: Haven't completed prerequisites in Shopify Partner Dashboard.
Solution:
Review the Prerequisites section
Log in to Shopify Partner Dashboard
Create custom app for this merchant
Configure required API scopes
Generate and copy credentials
Return to Channel Dashboard to pre-register
Merchant Already Connected
Problem: Merchant tries to connect but sees "store already connected" error.
Cause: This store is already connected to your channel (check "Connected Merchants" tab).
Solution:
If merchant needs a fresh connection, delete the existing connection first
Create a new pre-registration
Send new link to merchant
Frequently Asked Questions
Migration & Timeline
Do we need to migrate all existing custom apps immediately?
No. Existing merchant-created custom apps continue working indefinitely. Only migrate when you need to:
Change permissions
Rotate credentials
Set up a new merchant
Can merchants still access their existing custom apps?
Yes. They can view them in Settings > Apps and sales channels, and they can uninstall them if needed. They just can't create new ones after January 1, 2026.
What happens to my old Shopify integrations?
Old integrations: Merchants connected before January 2026 will continue to work as-is. No changes needed for existing merchants.
New onboarding: All new merchants must follow the pre-registration process in this guide.
Why did Shopify require this change?
Shopify deprecated the previous channel-controlled custom app model to give merchants better security and control. With single-merchant custom apps:
Each merchant owns their app and credentials
Merchants can revoke access at any time
Merchants have full visibility into API permissions
Better audit trail for data access
Merchants have full control over their integrations
Permissions & Scopes
What if a merchant needs additional permissions?
You must create a new single-merchant app with the expanded permissions and send them a new installation link. The old app will continue working until they're ready to switch.
Permission changes require:
Update the custom app in Shopify Partner Dashboard to include additional scopes
Create a new pre-registration with the updated credentials
Have merchant reinstall using the new link
Do we need to update our API version?
Not necessarily. Single-merchant apps work with any stable API version. However, it's good practice to use recent versions (2025-10 or later).
App Management
Can one single-merchant app be installed on multiple stores?
No. Each single-merchant app is designed for exactly one merchant. You need to create separate apps for each merchant, even if they're owned by the same company.
How do we handle merchants who create new stores after January 1, 2026?
You'll need to create a new single-merchant app and send them the installation link for each new store.
Can we automate app creation via API?
Shopify doesn't currently provide an API to create single-merchant apps programmatically. You must create them through the Partner dashboard. Violet will proactively notify you if this changes.
What if we have hundreds of merchants?
This is time-intensive but manageable:
Create apps in batches
Prioritize based on need
Remember that existing apps don't require immediate migration
Establish a process for creating new apps efficiently
Credentials & Security
I lost my Client Secret or forgot to copy it before navigating away
The Client Secret appears only once in Shopify. If you didn't copy it, you'll need to regenerate it:
Go to Shopify Partner Dashboard → App Distribution
Navigate to your Custom App → select View on Dev Dashboard (far right link)
Navigate to the API credentials section
Find the Client Secret field and click Rotate

Copy the new Client Secret immediately
Return to Violet Channel Dashboard
Edit the pre-registration for this merchant (Actions menu → Edit)
Update the Client Secret field with the new value
Save the pre-registration
If the merchant already started installation with the old credentials, send them the updated installation link
What happens to our existing API credentials?
They continue working unchanged. The access tokens from merchant-created custom apps remain valid.
Pre-Registration
Can I edit a pre-registration after creating it?
Yes. Use the Edit action in the Pre-Registered tab to update:
Merchant Name
Store URL
Client ID
Client Secret
Important: If a merchant has already started installation, editing credentials will require them to reinstall with updated credentials.
How do I know when a merchant has completed installation?
The merchant automatically moves from the "Pre-Registered" tab to the "Connected Merchants" tab. You'll see them appear in your Connected Merchants list, and their status will change from "Pending" to "Active".
Can I pre-register the same merchant multiple times?
No. Each store URL can only have one active pre-registration. If you need to create a new pre-registration:
Delete the existing one (Actions menu → Delete)
Create a new pre-registration with the updated credentials
Send new installation link
What is the Install Link and where do I find it?
The Install Link is a Shopify-generated URL that allows merchants to install your custom app directly in their Shopify admin.
Format: https://admin.shopify.com/store/{store}/oauth/install_custom_app?client_id=...
Where to find it:
Navigate to App Distribution → Select your custom app
Click on the Distribution section
If you haven't selected a distribution method, click "Select distribution method" and choose "Custom distribution"
The Install Link appears on the Distribution page with a Copy button
When you need it: The Install Link is required when creating a pre-registration in Violet Channel Dashboard. It's also what you send to merchants FIRST, before the Violet Connect link.

Why do merchants need to install the app before using Violet Connect?
The two-step process (Install Link, then Violet Connect) is required because:
Shopify requirement: Custom apps must be installed in the merchant's Shopify admin before OAuth can complete
App authorization: The Install Link triggers Shopify's app installation flow, which grants the necessary permissions
OAuth handshake: Violet Connect then completes the OAuth process using the pre-registered credentials
The correct order is:
Channel sends Shopify Install Link to merchant
Merchant installs app in Shopify admin
Channel sends Violet Connect link to merchant
Merchant completes Violet onboarding
Skipping step 2 will cause errors during Violet Connect onboarding.
Costs & Billing
Are there any cost changes?
Single-merchant apps (custom apps) remain free. There's no cost difference between old and new custom apps.
Installation Flow Diagram
Additional Resources
Official Shopify Documentation
Violet Documentation
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