Apple OS X system installation or update what happens when the installation process is compromised?

How to troubleshoot "Installation process corrupted" or "copy of program not verified" in OS X system installation or update "OS X Yosemite Application copy cannot verify", or "may have been corrupted or tampered with during the download", often occurs during OS X Yosemite installation. Sometimes simple reboots or reinstallation can solve the problem. However, if the problem continues to occur repeatedly, you can fix the problem by modifying the MAC system date.

1, the OS X Yosemite system of any program installation is likely to have similar problems, may be Apple Store update, network recovery, program uninstall and so on. If a user encounters this problem with an OS X installation or update in the Apple Store, you can click  to enter the Apple menu > System Preferences > Date & Time and choose to automatically adjust the date and time to solve the problem. The operation must be guaranteed to have network access. If there is no network, go to the terminal for date setting.

2, to determine if the terminal Date setting resolves the issue reinstall OS X, the user needs to install OS X boot menu > command line, pull down Utility menu option, select ' Terminal ', and enter the following command: Date hit Enter, if the report date is the current date, Then we can find out the cause of the problem, as the picture shows: Mon 09:55:15 PST 1984 is very important in this line, thinking that only the date is correct to successfully install OS X, if the change date encounters OS X's release period, then this error occurs, so the year is important. If the time is wrong, there are two ways to set, you can set to automatically adjust the date, through the network settings to be simple and convenient: ntpdate-u time.apple.com If the MAC does not have network access, this setting is not possible, so users need to use manual settings. If the user is familiar with the command line, you can use the date-help to retrieve it. This date format may be a bit weird to open-"[Mm]dd]hh]mm[[cc]yy]", in fact, "Month Day", which is a row of fixed format, can not be added between the number of spaces and other symbols, such as the date set to: "September 2016 at 17:33′′, the user can see the following syntax: Date 0920173316 This looks like a random set of numbers, but it's actually the month 09, time 1733, year 16, and several times.

3, once entered the date click Enter, you can exit the terminal, start OS X installation, and no longer have the above problems.