When you want to have the ability of verifying the integrity of your documents, you can digitally sign them. If your files are modified the embedded digital signature will become invalid and will indicate that file has been changed, has become corrupt or has somehow damaged. Similarly, you can add a timestamp to your files which can be used to verify that these files existed at a certain date and time.
For digital signing your documents, for time-stamping the files and for verifying the digital signature, or time-stamp, you can use free software XolidoSign desktop software. It supports all types of files including plain TXT, PDF, Microsoft Word, Microsoft Excel, Microsoft PowerPoint, Microsoft Access, PHP, HTML, 3D files, vector graphic files, audio, video and image files among many others. All these type of files can be digitally signed and time-stamped.
In order to digitally sign the documents, you have to add the files that are to be processed, select an electronic certificate installed on your computer. This electronic certificate is not free and has to be purchased from a digital certificate issuing authority. But for time-stamping files, you won’t need any such electronic certificates. You can time-stamp your files freely and generate proof that they existed at the time of time-stamping.
XolidoSign can also be used to verify your documents. For this, you can select all the documents or files that you wish to verify and then click on the “start process” button. When a document is successfully verified, it will display indication in green color. If verification fails, then warning is shown in red color.
XolidoSign makes it very easy for anyone to digitally sign their documents. It can also time-stamp your files and create proof of their existence at a certain point in time.
You can download XolidoSign from https://en.xolido.com/lang/xolidosign/xolidosigndesktop/.