I have this same problem: "Service registration is missing or corrupt"
I ran the fix it from http://support.microsoft.com/kb/971058
And it returned this report:
| Windows Update | Publisher details |
|---|
| Issues found | Issues found | Issues found | ||||||
|---|---|---|---|---|---|---|---|---|
| Service registration is missing or corrupt | Not fixed | ![]() |
||||||
| Reset service registration | Succeeded | ![]() |
<br> | --- | --- | --- | ||
| Check for missing or corrupt files | Fixed | ![]() |
||||||
| Repair missing or corrupt files | Succeeded | ![]() |
<br> | --- | --- | --- | ||
| Windows Update error 0x8007000D(2013-11-30-T-02_27_46P) | Fixed | ![]() |
||||||
| Resetting Windows Update data store | Succeeded | ![]() |
<br> | --- | --- | --- | ||
| Problems installing recent updates | Fixed | ![]() |
||||||
| Repair Windows Update | Succeeded | ![]() |
<br> | --- | --- | --- |
| Issues checked | Issues checked | Issues checked |
|---|---|---|
| Windows Update environment variables are incorrect | Checked | ![]() |
| Some security settings are missing or have been changed<br><br><br>Some security settings are missing or have been changed | Checked | ![]() |
| Corrupt Patch Registry keys | Checked | ![]() |
| Windows Update services are not running | Checked | ![]() |
| Cryptographic service components are not registered | Checked | ![]() |

