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# Can't add card or pay? Stripe payment form not loading (js.stripe.com/v3 blocked)

**Symptoms this article covers:** "Add card" or "Change payment method" shows an endless spinner; the Stripe form is blank; you see "We couldn't load the payment form"; browser shows `ERR_INTERNET_DISCONNECTED` on `https://js.stripe.com/v3/`; you can sign in fine but can't pay or upgrade; works on your phone but not on your computer.

Almost every "payment won't load" report is the same thing: your browser can't reach `https://js.stripe.com/v3/` - the specific Stripe SDK URL SimplyPrint loads. SimplyPrint uses Stripe for all payments, and `js.stripe.com/v3` is a common target for ad-blockers, antivirus, and corporate firewalls.

## 5-second test
Open this URL in a new tab in the **same** browser: [https://js.stripe.com/v3/](https://js.stripe.com/v3/)

- **You see a wall of JavaScript:** Stripe is reachable. Hard-refresh SimplyPrint (`Ctrl + Shift + R` / `Cmd + Shift + R`) and try again.
- **You see "This site can't be reached" or "ERR_INTERNET_DISCONNECTED":** Stripe is blocked. Continue below.

## What blocks Stripe
- **Aggressive ad-blockers** (uBlock Origin with custom filters, Privacy Badger, NoScript)
- **Antivirus HTTPS scanning** (Kaspersky, Avast, AVG, Bitdefender)
- **VPNs with ad-blocking tiers** (NordVPN, Surfshark, Proton)
- **Pi-hole, AdGuard Home, NextDNS** with aggressive blocklists
- **Corporate firewalls** that whitelist a small set of "approved" domains
- **School / enterprise networks** that block payment traffic by policy

## What to do (in order)

### 1. Hard refresh
`Ctrl + Shift + R` / `Cmd + Shift + R`. Often fixes a half-loaded form.

### 2. Incognito with extensions OFF
In Chrome, extensions are NOT auto-disabled in incognito - you must check each one. If the form loads in incognito with extensions off, see [Browser extensions blocking SimplyPrint](https://help.simplyprint.io/en/article/browser-extensions-blocking-simplyprint-ublock-privacy-badger-ad-blockers-19369uy/).

### 3. Try another browser
Chrome, Firefox, Edge. Works in another browser = browser-specific setting, extension, or profile corruption in your usual one.

### 4. Update your card from your phone (the easiest workaround)
This is the practical fallback. If `js.stripe.com/v3` is blocked specifically on your computer (antivirus, VPN, corporate firewall), your phone on mobile data is on a completely different network.

1. Open [simplyprint.io/panel](https://simplyprint.io/panel) on your phone.
2. Sign in.
3. Add or update your card.
4. Once saved, you can continue using everything else on your computer.

### 5. Allowlist Stripe in your antivirus / firewall
If you control your network or antivirus, allow these Stripe domains:

- `js.stripe.com`
- `m.stripe.com`
- `r.stripe.com`
- `api.stripe.com`
- `q.stripe.com`

For corporate networks: your IT department needs to allow these. We can't bypass it - Stripe loads directly in your browser, not through our servers, and Stripe forbids us from proxying.

### 6. Use invoiced payments instead (Print Farm, School, Enterprise)
If Stripe is permanently blocked for policy reasons on your network, [switch to invoiced payments / bank transfers](https://help.simplyprint.io/en/article/switching-to-invoiced-payments-bank-transfers-dbwdpi/) instead. No Stripe involved.

## After the form loads
- [How SimplyPrint billing works (payment methods, currencies, invoices)](https://help.simplyprint.io/en/article/how-simplyprint-billing-works-payment-methods-currencies-and-invoices-b45c6x/)
- [Subscription payment method fees (PSD2)](https://help.simplyprint.io/en/article/subscription-payment-method-fees-psd2-hnq3so/) - if you see PSD2 / 3-D-Secure pop-ups
- [Subscription terminated after failed renewal](https://help.simplyprint.io/en/article/subscription-terminated-after-consecutive-failed-renewal-attempts-nql7cn/) - if the load failure caused a missed renewal

## Related
- [SimplyPrint won't load: blank screen, spinner, or stuck on login](https://help.simplyprint.io/en/article/simplyprint-wont-load-blank-screen-spinner-or-stuck-on-login-t76abf/)
- [Browser extensions blocking SimplyPrint](https://help.simplyprint.io/en/article/browser-extensions-blocking-simplyprint-ublock-privacy-badger-ad-blockers-19369uy/)
- [Send a debug report to SimplyPrint support](https://help.simplyprint.io/en/article/send-a-debug-report-to-simplyprint-support-when-nothing-else-works-azsvh0/)