SQL Server is installed many times, the first time I met such a problem:
TITLE: Microsoft SQL Server 2008 R2 Setup
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The following error occurred:
An error occurred during the installation of assembly 'Microsoft.VC80.CRT,version="8.0.50727.42",type="win32",processorArchitecture="amd64",publicKeyToken="1fc8b3b9a1e18e3b"'. Please refer to Help and Support for more information.
For help, click: http://go.microsoft.com/fwlink?LinkID=20476&ProdName=Microsoft+SQL+Server&EvtSrc=setup.rll&EvtID=50000&ProdVer=10.50.1600.1&EvtType=0xDF039760%25401201%25401
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BUTTONS:
OK
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As shown below:
To solve this problem, refer to the https://social.msdn.microsoft.com/Forums/sqlserver/en-US/ea68f38e-98d6-4e4e-ad3c-02538da68720/instalation-error
mean to say the problem is due to the assembly Microsoft.VC80 .CRT lead to inconsistent versions to download something installation:
https://www.microsoft.com/en-us/download/details.aspx?id=5638
After the download is this stuff: 
Download Well, after the sqlserver installation program exits, install it!
May occur during the installation this question:
Second, the problem is "for the SQL Server consistency verification registry key" Status: Failed
Http://www.bubuko.com/infodetail-243742.html find solutions here, this time, do not quit the installer and let it stay for a while first, follow the steps below:
1. Open the Registry, find the [HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ Windows NT \ CurrentVersion \ Perflib \ 0804], respectively, to open the Counter and Help
2. Open the Counter, the scroll bar is pulled down last, and then note that the maximum value (not the same on different computers), close the window after a note
3. The same open Help, scroll to the last note of the maximum value (the value you do not necessarily like me oh !!!), close the window after a note
4. re-positioned on the node Perflib
5. Double-click Last Counter Value data is then input in Step 2 referred to maximum just under the Counter, and Help maximum noted in step 3, and select Decimal, OK
6. Then close the registry, return to the installation window click on the re-run, (general can solve, if you can not restart the installation).
After the installation is complete, re-install Sql Server on it, make the installation! ! !
借用别人的作业记录下，以防忘记