Problems Accessing Secure Website on Windows XP
 

Symptoms
You are using windows XP, and you cannot sign into msn messenger, or access secure websites, such as payment sites or internet banking.

Cause
This can be caused by a number of things, all of which are detailed below

Solution
All the information needed can be found in this Microsoft knowledgebase article

however, one of the most common cause is corruption failure of dll files, so to reregister these, do the following:

1. Click Start, and then click Run
2. In the Open box, type cmd, and then click OK.
3. At the command prompt, type the following lines and press ENTER after each line:
   regsvr32 softpub.dll
   regsvr32 wintrust.dll
   regsvr32 initpki.dll
   regsvr32 dssenh.dll
   regsvr32 rsaenh.dll
   regsvr32 gpkcsp.dll
   regsvr32 sccbase.dll
   regsvr32 slbcsp.dll
   regsvr32 cryptdlg.dll
4. Click OK when you receive the message that DllRegisterServer in FileName succeeded.
5. Type Exit

Then it should be all working :)

Article originally written by Monkeybreath