## Troubleshooting

### [What do the strange symbols on my mailing mean?](https://help.optilyz.com/en/support/solutions/articles/43000668324-what-do-the-strange-symbols-on-my-mailing-mean-)

Postage optimization / sorting at the post office You may discover small digits or number combinations in your mailings, often located above the sender ...

### [Why are there stains on my postcard?](https://help.optilyz.com/en/support/solutions/articles/43000706576-why-are-there-stains-on-my-postcard-)

One of the most common problems our customers notice with their delivered postcards is one or more streak-like marks on one or both sides of the card. But w...

### [Loading issues on the optilyz platform](https://help.optilyz.com/en/support/solutions/articles/43000608466-loading-issues-on-the-optilyz-platform)

Do you receive an error message when creating a mailing? z. B. "Something went wrong" (Google Chrome) Try the following options: Delete bro...

### [Why is the final price of my mailing different from the costs in the price calculator?](https://help.optilyz.com/en/support/solutions/articles/43000713168-why-is-the-final-price-of-my-mailing-different-from-the-costs-in-the-price-calculator-)

In general, our prices apply to mailings that are printed up to 60% in colour and 40% in black and white. If the mailing contains more colour or is even com...

### [How is optilyz affected by the xz backdoor?](https://help.optilyz.com/en/support/solutions/articles/43000725833-how-is-optilyz-affected-by-the-xz-backdoor-)

The xz backdoor vulnerability is a security flaw that has been identified on 29th of March 2024 in certain software systems. This backdoor allows unauthoriz...

### [Why do I have to enable cross-site cookies, and how do I do that?](https://help.optilyz.com/en/support/solutions/articles/43000725902-why-do-i-have-to-enable-cross-site-cookies-and-how-do-i-do-that-)

We’re aware of a current issue where browser settings default to disabling cross-site cookies. As our platform requires cross-site cookies for logins, you m...

### [Why can I not use AddressFactory for my mailing?](https://help.optilyz.com/en/support/solutions/articles/43000727669-why-can-i-not-use-addressfactory-for-my-mailing-)

Due to technical limitations, only mailings which are mapped to a number lower than individualisation80 can be processed for the AddressFactory option. ...

### [How to whitelist optilyz for third party cookies](https://help.optilyz.com/en/support/solutions/articles/43000774567-how-to-whitelist-optilyz-for-third-party-cookies)

This guide provides step-by-step instructions for whitelisting the optilyz domain to allow third-party cookies on Google Chrome, Mozilla Firefox, and Micros...