https://jeltsch.org/en/tags/protection/Recent content in Protection on Michael’s DomainHugoen-usCopyright © 2002 - 2026 Michael Jeltsch.Fri, 24 Jul 2026 00:18:18 +0300https://jeltsch.org/en/booster/Fri, 14 Jan 2022 00:00:00 +0000https://jeltsch.org/en/booster/<p>Hooray, I am finally boostered! I did not mind what I would get, but ended up for the 3rd time getting the BioNTech/Pfizer mRNA vaccine.UPDATE (23.01.2022):I received some feedback concerning this 2-sentence blog post. I never really think much about the vaccination anymore. To me, the situation appears very clear from a science-based medical perspective. Below, I will keep adding answers to some questions and statements.</p>https://jeltsch.org/en/removing_pdf_password_protection/Thu, 05 Apr 2007 00:00:00 +0000https://jeltsch.org/en/removing_pdf_password_protection/<p>I recently bought a pdf book. It was password-protected (40bit security). Unfortunately some of the PDF viewers on Linux cannot open password-protected pdf files. So I decided that I can remove the password protection for private use.A quick lock at the web showed two very easy methods of password removal:</p>