password protected Base64 string convert into pdf file without password - c#

I have Encrypted PDF File and i have convert encypted PDF file To Base64 string. I want Base64 string convert into PDF File (Means PDF file will write without password). PDF File should open.
Encrypted Base64 string is perfectly convert into pdf file but when i am trying to open the pdf file it is asking password.
I want when file is convert into Encryted base64 to PDF File then it should open without password .File is saving on my folder.
How i can do it. with asp.net with c#.


Can’t be done.
Otherwise the mere act of emailing a password protected PDF removes the protection and I’m pretty sure the payslips I get are protected.

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