WININET.DLL not found

When I try to open MS Internet Explorer I get the following message and it does not allow the program to open:

dwwin.exe - unable to locate component
This application has failed to start because wininet.dll was not found. Reinstalling the application may fix the problem.

I also get another error message occassionally that I'm not sure is realated:

Missing BMUpdate.exe

I have been running AVG's Free Version Antivirus with automatic updates.

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I followed your procedures in the Read & Run Me First posting with the following results (all downloads were obtained using a 2nd computer via internet & transferred to ailing computer with usb flash drive):

Step 0
No problems

Step 1
Uninstalled all unnecessary software
Emptied quarentine folder in AVG Free Version Antivirus
Emptied recycle bin
Downloaded, installed & ran CCleaner
Got the following error message when running CCleaner
C:\Program Files\CCleaner\winsys.ini
Line:
SpecialKey1=N_INT_TEMP
53-File not found: wininet

Step 2
Enabled viewing of hidden files, system files & file extensions

Step 3
Verified only AVG Antivirus being used
Microsoft's firewall only firewall being used

Step 4
Downloaded & installed GetRunKey and ShowNew tools (log files attached)
Downloaded SpyBot and installed
Did not use CounterSpy
Downloaded & installed AVG Anti-Spyware (log file attached)

Step 5
Rebooted in safe mode
Unplugged network connection to router
Closed all unnecessary software
Ran CCleaner - some files deleted but got same error message as above
Ran SpyBot but got error message - wininet.dll missing
Ran AVG Anti-Spyware and let it fix approx 90 files (quarentined then deleted - log file attached)

Step 6A
Could not use Bitdefender or Panda because the computer does not have internet access due to whatever the problem is.

Step 6B
Rebooted in normal mode
Ran getrunkey & shownew (log files are attached)

Step 6C
Checked sticky thread Special Removal Procedures but must admit to being a novice and not quite sure if they apply to my situation.
Decided to post a log because problem still exists.

Step 7
Downloaded, unzipped & renamed HiJackThis per instructions
Ran HiJackThis (will attach log file (4th file) in follow up thread because I can only post up to 3 in this one)

Step 8
Didn't follow yet until I get further feedback on what to do next

PLEASE HELP!

 

Here's a copy of the HiJackThis log file that I ran

 

Replacing the wininet.dll file took care of it. Thanks a million