If you lost the password for a important PDF file there are a few ways to help you bypassing the pdf security, so you can open your pdf file again. Mostly this kind of software is called a PDF password cracker / PDF password remover. Using this tools with their provided pdf cracking methods will enable yout to remove or bypass the pdf security password. The security password that prevents you from opening the file gets either removed or displayed in plain text.
There are different ways a PDF can be protected. The pdf file can just use a password or the whole data inside the pdf gets encrypted by the password. You needed different tools for all of this kinds of security protection. In the meanwhile there are very powerful PDF password removal tools that can handle any level of pdf password security.
It may happend that you download a pdf file from the internet and you cannot open it because of the missing password. You will see something like this message “PDF file is password-protected” and the file will not open until you put the password inside the textbox. A lot of files and pdfs you can download from the web are protected by some password. Also there are many downloads where you have to do some kind of online survey first before you get the password. It is really frustrating if you have done a 30 minnute survey and afterwards the pdf password isn’t shown to you. In this case just use a pdf password remover tool to break the password of any protected pdf file.