Frequently Asked Questions

Browse our catalog, select a book, and click "Buy Now" or add it to your cart. Complete checkout with your email and payment details. You will receive a download link immediately after payment.

We accept all major credit and debit cards (Visa, Mastercard, American Express) through our secure Stripe payment gateway. We also support Apple Pay and Google Pay.

No! All our products are digital eBooks delivered instantly via download link. There is no physical shipping involved, so you never pay shipping fees.

All prices are displayed in EUR (Euros). Your bank or card provider will automatically convert the amount to your local currency at their current exchange rate.

EU customers are charged VAT based on their country (ranging from 17-27%). Our Stripe integration automatically calculates the correct VAT rate. Non-EU customers may not be charged VAT.

Yes! An invoice is automatically generated for every purchase. You can download it from your order confirmation email or your account order history. Invoices include all necessary details for business expense claims.

Absolutely! During checkout, you can enter your company name and VAT number (if applicable). The invoice will be issued to your company. For bulk orders (10+ books), contact us for volume discounts.

Yes! Contact us at info@dargslan.com for team licenses and volume discounts. We offer special pricing for companies, educational institutions, and training organizations.

Yes! Payments are processed by Stripe, a PCI-DSS Level 1 certified payment processor. We never see or store your full card details. All transactions are encrypted with TLS/SSL.

Check that your card details are correct and has sufficient funds. Try a different card or payment method. If the issue persists, contact your bank as they may be blocking the transaction.

First, check your spam/junk folder. If not there, contact us with your order email and we will resend your download link immediately. Response time is usually within 1 hour during business hours.

Yes! New customers automatically receive a 10% discount on their first order. The discount is applied automatically at checkout - no coupon code needed. Welcome to Dargslan!

After purchase, you receive an order confirmation email with your order number. Log into your account and go to "Order History" to see all your orders, their status, and download links.

Yes! Many books offer a free sample chapter. Look for the "Download Sample" button on the book's product page. The sample gives you a preview of the content and formatting quality.

After purchase, you will receive an email with a secure download link. Click the link to access your download page where you can download files in all available formats (PDF, EPUB, source code).

Download links are valid for 7 days and allow up to 5 downloads per format. After 7 days, the link expires but you can request an extension from your account library.

Yes! You can request a download extension. We offer one free extension per order. Additional extensions are available for a small fee of €3.99 for 5 extra downloads.

Log into your account and go to My Library. Find the order and click "Request Extension". You get one free extension per order. You can also contact support with your order number.

Yes! Once downloaded, the files are yours to keep. You can copy them to any of your personal devices - computer, tablet, phone, e-reader. There is no DRM restriction.

If you have an account, log in and go to "My Library" to see all your purchases. You can re-download (if within limits) or request extensions. Keep your confirmation emails as backup.

Only to download the files initially. Once downloaded, the PDF and EPUB files are stored on your device and can be read completely offline.

Most books are available in PDF and EPUB formats. Many technical books also include source code files in a ZIP archive. Available formats are shown on each book's product page.

PDF maintains fixed formatting and is best for technical books with code/diagrams. EPUB is reflowable text that adapts to screen size, better for pure reading on e-readers and phones.

Yes! EPUB files can be converted to Kindle format using free tools like Calibre. Alternatively, you can email the PDF directly to your Kindle (check Amazon's Send to Kindle feature).

Absolutely! Use Apple Books (built-in) for EPUB files, or any PDF reader for PDFs. Simply download the file and open it with your preferred reading app.

Yes! Use Google Play Books, Moon+ Reader, or any PDF/EPUB reader app from the Play Store. Download the file and open it with your preferred app.

For EPUB: Apple Books (iOS/Mac), Google Play Books (Android), Calibre (desktop). For PDF: Adobe Acrobat Reader, Foxit Reader, or any built-in PDF viewer.

No, we do not use DRM. Once purchased, the files are yours without restrictions. We trust our customers and believe DRM-free provides a better reading experience.

Source code downloads contain all code examples from the book in a ZIP archive, organized by chapter. Includes README files with setup instructions where applicable.

No account is required for one-time purchases. However, creating a free account gives you access to your order history, download library, wishlists, and faster checkout.

Click "Sign In" in the header, then "Create Account". Enter your email and create a password. You can also create an account during checkout by checking "Create account".

Click "Sign In", then "Forgot Password". Enter your email address and we will send you a password reset link valid for 1 hour. Check your spam folder if you don't see it.

Log into your account, go to Profile settings. You can update your email address there. A verification email will be sent to confirm the change.

Submit a data deletion request on our Data Protection page. We will delete your account and personal data within 30 days as required by GDPR. Note: This does not affect past invoices which we must retain for legal reasons.

Accounts are for individual use only. For team access, contact us about team licenses. Sharing accounts violates our Terms of Service and may result in account suspension.

The wishlist lets you save books you want to buy later. Click the heart icon on any book to add it. Access your wishlist from the header icon. Great for tracking books during sales!

Enter your coupon code in the cart or checkout page in the "Coupon code" field and click "Apply". Valid discounts will be applied to your order total immediately.

Only one coupon code can be used per order. Choose the one that gives you the best discount. Coupons cannot be combined with each other.

Check: Is the code typed correctly? Has it expired? Does it meet minimum order requirements? Is it valid for the items in your cart? Contact support if you believe there's an error.

Visit our Gift Cards page, select an amount (€10-€200), and complete checkout. You can send it immediately or schedule delivery. Add a personal message for the recipient.

Enter your 16-character gift card code at checkout in the Gift Card field. The balance will be applied to your order. Any remaining balance stays on the card for future use.

Yes! Go to Gift Cards > Check Balance in the menu, enter your gift card code, and see your remaining balance. Balances never expire.

Yes! You can use both a gift card AND a coupon code on the same order. The coupon discount is applied first, then the gift card balance.

Bundles are curated collections of 3-5 related books at a significant discount (typically 20-40% off). They're created by our team around specific topics or skill paths.

Create your own bundle! Add 2+ books for automatic discounts: 2 books = 10% off, 3 books = 15% off, 4 books = 20% off, 5+ books = 25% off. Access it from Bundle Builder in the menu.

Visit our Free Books page, enter your email to subscribe to our newsletter, and receive an instant download link. One free download per email address. New free books added regularly!

We run seasonal sales (Black Friday, Christmas, New Year) and occasional flash sales. Subscribe to our newsletter to be notified first and get exclusive discount codes.

When viewing a book, you can click "Notify me when price drops" to receive an email if the book goes on sale. You can manage your price alerts from your account settings. We'll email you immediately when the price decreases!

Yes! If you added items to your cart but didn't complete checkout, we'll send you a friendly reminder email. These emails often include special discount codes to help you complete your purchase.

Click the "Unsubscribe" link at the bottom of any newsletter email. You'll be immediately removed from our mailing list. Note: This doesn't affect transactional emails (order confirmations, download links).

Use the search bar at the top of the page. Our intelligent search understands synonyms and related terms. You can search by title, author, topic, or keywords. Results are ranked by relevance.

Browse our 3-level category hierarchy in the left sidebar. Categories are organized from broad topics to specific specializations. Click any category to see all books within it.

As you browse, we remember which books you've looked at. The "Recently Viewed" section appears on book pages, helping you quickly return to books you were interested in. This data is stored only on your device.

After purchasing a book, go to that book's page and scroll to the Reviews section. Click "Write a Review", select your star rating (1-5), and write your review. Reviews are moderated before appearing publicly.

Yes! Customer reviews and ratings are displayed on each book's product page. We show the average rating and individual reviews to help you make informed purchasing decisions.

Tags are keywords that describe a book's content (e.g., "Python", "Machine Learning", "Beginner"). Click any tag to see all books with that tag. Tags help you discover related content.

Based on your cart items and browsing history, we suggest related books you might enjoy. These cross-sell recommendations help you discover complementary content in your areas of interest.

Our exit-intent popup offers exclusive deals to first-time visitors! If you were about to leave, we might offer you a special discount code. Subscribe to our newsletter through the popup to receive the offer.

Featured: Hand-picked recommendations by our team. Bestseller: Top-selling books based on sales data. New Release: Recently published books. Sale: Books currently discounted from their regular price.

Try: 1) Different browser (Chrome, Firefox, Edge), 2) Disable download blockers/ad blockers, 3) Check your Downloads folder, 4) Try right-click > Save Link As. Contact support if still not working.

Re-download the file using your download link. If you've used all downloads, request a free extension. If the file is still corrupted, contact support with your order number.

Make sure you're viewing at 100% zoom. Some PDF readers default to lower quality for faster loading. Check your reader's quality/rendering settings.

Windows 10/11 can open ZIP files natively. For Mac, double-click the file. If issues persist, use free software like 7-Zip (Windows) or The Unarchiver (Mac).

Check the README file included in the ZIP for setup instructions. Ensure you have the required software versions installed. Check our book's errata page for known issues and fixes.

Thank you for helping us improve! Please contact us via the Contact page with the book title, page number, and description of the error. We maintain errata pages for all books.

Minor updates and errata fixes are provided free to existing customers. For major new editions, we offer existing customers a significant upgrade discount.

Visit our Contact page or email info@dargslan.com. Include your order number for faster service. We respond within 24 hours during business days (Mon-Fri, 9AM-6PM CET).

We currently offer support via email and our contact form only. This allows us to provide detailed, documented responses. Most inquiries are resolved within 24 hours.

Digital products are non-refundable once downloaded per EU Directive 2011/83/EU Article 16(m). If you haven't downloaded and have issues, contact us within 14 days. See our full Refund Policy.

Due to the nature of digital products, we cannot accept returns once the file has been downloaded. If you received the wrong file or it's corrupted, contact us for assistance.

Each purchase is licensed for personal use only. Sharing, distributing, or reselling our eBooks is prohibited. For team access, please contact us about team licenses.

We comply fully with GDPR. We collect only necessary data, encrypt all transmissions, never sell your data, and use industry-standard security. See our Privacy Policy for full details.

We collect: email, name (if provided), order history, and necessary payment data. We do NOT store credit card numbers. Analytics data is anonymized. See our Privacy Policy.

Yes! Under GDPR Article 15, you can request a copy of all data we hold about you. Submit a request on our Data Protection page and we'll respond within 30 days.

Yes! Under GDPR Article 17, you have the right to erasure. Submit a request on our Data Protection page. Note: We must retain invoice data for 10 years per tax law.

Yes. Essential cookies for site function (cart, login) are always used. Analytics and marketing cookies require your consent. Manage preferences via Cookie Settings in the footer.

Dargslan s.r.o. is a Slovak company specializing in technical eBooks. Visit our About page and Impressum for full company details, registration numbers, and contact information.