After some time of not using TeamViewer I'm surprised that now it is now working anymore, whenever I try to open or re-install TeamViewer it is giving me this error.

Critical Error!
Verification of your TeamViewer version failed!
TeamViewer will quit for security reasons. Please reinstall TeamViewer.
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Hi there,
When you don't use your any software for a while they become corrupt even you don't make any changes to them!!
It's just because of some temporary file coming from the internet that corrupts the software!!
You have to completely uninstall the software from Uninstalling a program utility in Control Panel,
After that go to your Program Files x86 folder and search for "TeamViewer" folder and remove it.... Reboot your PC.
Now again download fresh updated version of TeamViewer and install it, again reboot your system and try it!
Hope it works!
Hello,
Jody Akerly,
GOOD Day
First you should test your hard disk and memory.
Besides the regular hard disk and memory testing, you should done checking a system file (sfc/scannow)btw, Correct the computer date and time.
To check system file click start and type cmd and then type the above command
After checking the above indication when you check system file you will find this
Fixed it and repair the installation.
GOOD LUCK....
Hello Jody,
Team Viewer may be blocked by security applications that you have on your computer and therefore it is not able to execute properly. You will therefore need to do the following:
Regards,
Carl
When you encounter a verification error on your application there are times you may associate it with data corruption or more precisely it’s possible that one of its data files has been corrupted that caused the error. Verification problem may also be caused of files not loading properly. If this is the case try restarting the program. If it’s still the same, re-install the program then see if it works again.
If this still didn’t fix the problem, it’s maybe because of a problem in the certificate it uses which is obviously used for the verification of the product. To have a possible fix using the application’s certificate, go to the installation folder of your application “C:\Program Files\TeamViewer\Version7\” then locate the main executable of the program “TeamViewer.exe”. Right-click on the file then select “Properties”.
Select “Digital Signatures” tab then click the signature under “Signature list” to select then click “Details”. In “General” tab click “View Certificate” then on the next window click “Install Certificate” to install the present certificate of the program. If installing the program’s certificate still didn’t help, it would be best now to upgrade your software to the latest version. It’s possible that the software’s present digital signatures or the certificate is already invalid and got expired during those times you are not using it.
Regards
Sharath Reddy