Reader 10.1 Freezing Browsers

Question

We're using Reader 10.1 in protected mode on XP SP3 machines.  Browsers used are FF4/5, and IE 8.
When a user navigates to a site with a pdf and opens it, Reader opens in protected mode by default which is what we want.  When you click on "save a copy" at the bottom, the save as box pops up and will randomly freeze the browser.  When it does freeze, it will not let you browse to a different directory to save or even cancel the attempted saving operation.  Clicking cancel will typically kill this box after about 60 seconds.  All browsers listed appear to be affected by this.  Task manager doesn't show a spike in CPU/memory use and nothing abnormal in event viewer logs.
On one test machine FF will freeze while IE will work fine.  Try again later and FF is fine and IE freezes.  Sometimes it happens.  Sometimes it doesn't.  AcroRd32.exe has been verified as not running in between tests.  Reader functions normal when opening a pdf locally.
Bringing Reader out of protected mode (click on Adobe logo in lower right corner) and then selecting "save a copy" works and no problems reported.
It sounds similar to:
http://kb2.adobe.com/cps/860/cpsid_86063.html
Specific JavaScript API usage doesn't work
The JS SaveAs  function fails: doc.saveAs() fails due to security restrictions.  Protected Mode prevents scripts running inside Reader from writing to  locations except for %temp% and the AppData area for Reader X.
Any suggestions on a fix?

Answer 1

This is what was generated in the log file:
[07:07/14:43:38] Adobe Reader Protected Mode Logging Initiated
[07:07/14:43:38] Found custom policy file: C:\Program Files\Adobe\Reader 10.0\Reader\ProtectedModeWhitelistConfig.txt
[07:07/14:43:38] NtCreateKey: STATUS_ACCESS_DENIED
[07:07/14:43:38] real path: \REGISTRY\MACHINE\Software\Adobe
[07:07/14:43:38] Consider modifying policy using this policy rule: REG_ALLOW_ANY
[07:07/14:43:38] NtCreateKey: STATUS_ACCESS_DENIED
[07:07/14:43:38] real path: \REGISTRY\MACHINE\SOFTWARE\Adobe
[07:07/14:43:38] Consider modifying policy using this policy rule: REG_ALLOW_ANY
[07:07/14:43:38] NtCreateMutant: STATUS_ACCESS_DENIED
[07:07/14:43:38] real_path: \BaseNamedObjects\MSCTF.GCompartListMUTEX.DefaultS-1-5-21-1177238915-796845957-725345543- 3025
[07:07/14:43:38] Consider modifying policy using this policy rule: MUTANT_ALLOW_ANY
[07:07/14:43:38] NtCreateMutant: STATUS_ACCESS_DENIED
[07:07/14:43:38] real_path: \BaseNamedObjects\MSCTF.GCompartListMUTEX.DefaultS-1-5-21-1177238915-796845957-725345543- 3025
[07:07/14:43:38] Consider modifying policy using this policy rule: MUTANT_ALLOW_ANY
[07:07/14:43:39] NtCreateKey: STATUS_ACCESS_DENIED
The account that I am using has admin rights.