administrator has set policies against installation update of program

I have a program called vueminder calendar. It's been installed for about a year and has gone through several updates, but for some reason this update came up saying your computer has set administrator policies against installation. I am the administrator of my computer and I'm the only one who uses it. I'm not sure what could have changed. I've tried turning off my Norton 360 antivirus, I've also scanned for viruses, and I've made sure that all of my computer updates are installed. I'm not particularly fond of wanting to try re-installing anything. Ideas?

Windows 7 home premium SP1 64-bit
HP Pavilion dv6

Follow the methods listed below:
Method 1:
Follow the steps mentioned below and check if that fixes the issue:
1. Open control Panel and go to Administrative Tools.
2. In Administrative tools open Local Security Policy.
3. In Local Security Policy right click Software Restriction Policies and click “New Software Restriction Policy”.
4. Now Left click on software restriction policies and in the right-hand window you should see enforcement.
5. Double-click on enforcement and set the policy to apply to “ALL USERS EXCEPT LOCAL ADMINISTRATORS”
Approve the changes and check if you’re able to uninstall.
Method 2:
1. Click Start, type regedit and hit Enter.
Locate the following:
HKLM\Software\Policies\Microsoft\Windows\Installer
Create: DisableMSI Type: REG_DWORD value = 0 (0 should allow you to install)
2. Browse to HKEY_CLASSES_ROOT\Installer\Products\

Browse through and find your product. Delete the key relating to your product and this should allow the application to install.
In Windows 7, to turn off User Account Control (UAC) settings, you would have to move the slider to “Never notify me”. This selection disables UAC.
Note: You must restart your computer when you enable or disable UAC. Changing levels of notification does not require that you restart your computer.
Refer the link below for more information:
How do I change the behavior of User Account Control by using the slider?
http://windows.microsoft.com/en-US/windows7/How-do-I-change-the-behavior-of-User-Account-Control-by-using-the-slider
What are User Account Control settings?
http://windows.microsoft.com/en-us/Windows7/What-are-User-Account-Control-settings
Hope this helps!