Yes, but it is possible to recover a lost 7-Zip password, and this success depends on the complexity of the password. Some common ways to do this include:

1. Brute Force Attack
This is a trial of every combination possible until the right password is obtained. For this method, one can use 7-Zip Password Recovery or Stella Advanced Archive Password Recovery software.

2. Dictionary Attack
This method will guess the password by using predefined words or phrases in a list. It will be more effective than brute force if the password is somehow simple.

3. Mask Attack
If you are able to remember part of the password, perhaps its length or specific characters used, you might use this type of attack by limiting the combination and making recovery easier.

For more info visit this page- https://www.stelladatarecovery.com/7z-password-recovery.html