i updated my windows vista to windows 7. A few days later i receive this kind of warning when i start ang shutting down my computer. i also cant execute the windows task manager., "logonui.exe-system error. The program cant start because credui.dll is missing from ur computer. try reinstalling the program to fix this problem"
Does it say you need permission from "Trusted Installer"? If so, do the following-
1. Please navigate to the "Windows" folder. 2. Right-click on the file/folder and choose Properties. 3. Click the "Security" tab and see if your current user is listed in the "Group or user names" list. If not, please click Edit-> Add button, type the name of your current user in the "Enter the object names to select " box, then click "OK" to add this group. 4. Select the user from the list and then check the "Allow" checkbox next to "Full Control". 5. Click the Advanced button and click the "Owner" tab. Then, press "Edit" button. 6. Select current user from the list and check the "Replace owner on subcontainers and objects" checkbox. 7. Click "OK" to save changes and wait for Windows 7 to transfer the ownership of all the objects on the partition. 8. Click OK again to save changes and exit the Properties window.
Then click Start>Run>type "regsvr32 credui.dll" (without the quotes) to register the file to the system.
Or you can type cmd in the search box. Right click "cmd.exe" at the top of the search result page. And left click "Run as Administrator".
In the command prompt that opens up, copy/paste- regsvr32 credui.dll Then press enter.
You'll be told that the file has been successfully registered.
Is this happening to all applications, or just Avast?
What's happening IMO is the application is misinterpreting the operating system version and is trying to call a procedure in a previous Windows version of the Dynamic Link Library (DLL) that is unavailable in Windows 7.
This is precisely why one should always do a fresh install rather than upgrade from a previously installed version.
You can try the following-
Start>cmd> Right click on cmd.exe>Left click on Run as administrator>Type "sfc /scannow" without the quotes. Leave a space between sfc and the slash. Copy/paste if you want to.
If nothing else works, just re-format and do a fresh install after backing up your documents.
1. You can reboot to safe mode and remove recently installed softwares and try
again. If not working, you can boot to Last Known Good Configuration.
For that, start/restart your PC. When the initial Dell/HP/Lenovo logo is displayed (or motherboard logo if your's is an assembled PC) press and hold your "F8 Key" which should bring up the "Windows Advanced Options Menu". Use your arrow keys to move to "Last Known Good Configuration" and press your Enter key.
If that doesn't work, this definitely will....!
Step 1: Go to Start, Control Panel and click on System.
Step 2: Now click on the Advanced tab and under Performance, click on Settings.
Step 3: Click on Data Execution Prevention and select the Turn on DEP for all programs and services except for those I select: radio button.
Step 4: Now click the Add button and browse to C:\Windows\System32 and choose the regsvr32.exe file. When you get the message stating it could make your computer become unprotected and vulnerable to attacks, just click OK to continue.
Click OK and then click OK again to exit. Now try to run the regsvr32 command again from the command line and you should hopefully not get this error!