If you've ever dealt with the error message above, you know how much of a pain in the neck it can be. Well, if you're using ESET NOD-32 as your antivirus, and it's either version 2 or 4 (not 3 for some reason), there are known issues now in the Cisco TAC database. For a simple work around, try the following (this was done on NOD32 version 4):

<!--    [if gte mso 9]&gt;  Normal 0     false false false  EN-US X-NONE X-NONE              MicrosoftInternetExplorer4              &lt;![endif]--><!--    [if gte mso 9]&gt;                                                                                                                                            &lt;![endif]-->
<p class="MsoListParagraph" style="text-indent: -0.25in;"><!--    [if !supportLists]--><span style="font-size: 10pt; color: #c00000;"><span>1.<span style="font-family: &quot;Times New Roman&quot;; font-style: normal; font-variant: normal; font-weight: normal; font-size: 7pt; line-height: normal; font-size-adjust: none; font-stretch: normal; -x-system-font: none;"> </span> </span> </span> <!--    [endif]--><span style="font-size: 10pt; color: #c00000;">From within the NOD-32 main settings page-- Antivirus and Spyware </span> <span style="font-size: 10pt; font-family: Wingdings; color: #c00000;">à</span> <span style="font-size: 10pt; color: #c00000;"> Protocol Filtering </span> <span style="font-size: 10pt; font-family: Wingdings; color: #c00000;">à</span> <span style="font-size: 10pt; color: #c00000;"> SSL </span> <span style="font-size: 10pt; font-family: Wingdings; color: #c00000;">à</span> <span style="font-size: 10pt; color: #c00000;"> &quot;Always scan SSL protocol&quot; </span></p>
<p class="MsoListParagraph" style="margin-left: 1in; text-indent: -0.25in;"><!--    [if !supportLists]--><span style="font-size: 10pt; color: #c00000;"><span>a.<span style="font-family: &quot;Times New Roman&quot;; font-style: normal; font-variant: normal; font-weight: normal; font-size: 7pt; line-height: normal; font-size-adjust: none; font-stretch: normal; -x-system-font: none;"> </span> </span> </span> <!--    [endif]--><span style="font-size: 10pt; color: #c00000;">This is a temporary setting, which makes step 2 “un-grayed out”</span></p>
<p class="MsoListParagraph" style="text-indent: -0.25in;"><!--    [if !supportLists]--><span style="font-size: 10pt; color: #c00000;"><span>2.<span style="font-family: &quot;Times New Roman&quot;; font-style: normal; font-variant: normal; font-weight: normal; font-size: 7pt; line-height: normal; font-size-adjust: none; font-stretch: normal; -x-system-font: none;"> </span> </span> </span> <!--    [endif]--><span style="font-size: 10pt; color: #c00000;">Next, you go to Web Access Protection </span> <span style="font-size: 10pt; font-family: Wingdings; color: #c00000;">à</span> <span style="font-size: 10pt; color: #c00000;"> HTTP/HTTPS </span> <span style="font-size: 10pt; font-family: Wingdings; color: #c00000;">à</span> <span style="font-size: 10pt; color: #c00000;"> Change to &quot;Do Not Use HTTPS Protocol Checking&quot; </span></p>
<p class="MsoListParagraph" style="margin-left: 1in; text-indent: -0.25in;"><!--    [if !supportLists]--><span style="font-size: 10pt; color: #c00000;"><span>a.<span style="font-family: &quot;Times New Roman&quot;; font-style: normal; font-variant: normal; font-weight: normal; font-size: 7pt; line-height: normal; font-size-adjust: none; font-stretch: normal; -x-system-font: none;"> </span> </span> </span> <!--    [endif]--><span style="font-size: 10pt; color: #c00000;">This option is grayed out if you do not enable SSL protocol scanning as described in step 1</span></p>
<p class="MsoListParagraph" style="text-indent: -0.25in;"><!--    [if !supportLists]--><span style="font-size: 10pt; color: #c00000;"><span>3.<span style="font-family: &quot;Times New Roman&quot;; font-style: normal; font-variant: normal; font-weight: normal; font-size: 7pt; line-height: normal; font-size-adjust: none; font-stretch: normal; -x-system-font: none;"> </span> </span> </span> <!--    [endif]--><span style="font-size: 10pt; color: #c00000;">Last, go back to Antivirus and Spyware </span> <span style="font-size: 10pt; font-family: Wingdings; color: #c00000;">à</span> <span style="font-size: 10pt; color: #c00000;"> Protocol Filtering </span> <span style="font-size: 10pt; font-family: Wingdings; color: #c00000;">à</span> <span style="font-size: 10pt; color: #c00000;"> SSL </span> <span style="font-size: 10pt; font-family: Wingdings; color: #c00000;">à</span> <span style="font-size: 10pt; color: #c00000;"> &quot;DO NOT SCAN SSL PROTOCOL&quot;</span></p>
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This solved a nagging issue for a customer, and hopefully can save you some time in troubleshooting!