What steps will reproduce the problem?
Prob# 1.Click on player name and select "Whisper"
Prob# 2. Using 'General' chat window for WoW - not WIM - select any of the chat options such as Whisper, Guild, Say., a text line is received but when you type the text and press 'Enter' it does not display. This only happens when WIM is active. And curiously does not apply to 'Yell'. Yell will display.

What is the expected output? What do you see instead?

Prob #1. Expected: New WIM popup window for whisper
Prob #1. Instead: Lua error popup window 'window handler' copied below.

Prob #2. Expected: Receive a text line, type your message, press 'enter' and message is displayed.
Prob #2. Instead: A text line is received but when you type the text and press 'Enter' it does not display. This only happens when WIM is active. And curiously does not apply to 'Yell'. Yell will display correctly. ALSO: Lua error popup window copied below.

What version of the product are you using?
new 3.7.9 r518  10.26.16

Do you have an error log of what happened?
Prob #1 = Lua content:
Message: Interface\AddOns\WIM\Sources\WindowHandler.lua:709 WIM3_msgFrame1ScrollingMessageFrame doesn't have a "OnMessageScrollChanged" script
Time: 10/27/16 11:33:54
Count: 1
Stack: [C]: in function `GetScript'
Interface\AddOns\WIM\Sources\WindowHandler.lua:709 in function <Interface\AddOns\WIM\Sources\WindowHandler.lua:704
Interface\AddOns\WIM\Sources\WindowHandler.lua:1226 in function <Interface\AddOns\WIM\Sources\WindowHandler.lua:788
Interface\AddOns\WIM\Sources\WindowHandler.lua:1367 in function <Interface\AddOns\WIM\Sources\WindowHandler.lua:1317
(tail call): ?
Interface\AddOns\WIM\Modules\WhisperEngine.lua:192 in function <Interface\AddOns\WIM\Modules\WhisperEngine.lua:178
Interface\AddOns\WIM\Modules\WhisperEngine.lua:612 in function <Interface\AddOns\WIM\Modules\WhisperEngine.lua:572
[C]: in function `ChatEdit_ExtractTellTarget'
Interface\FrameXML\ChatFrame.lua:4271 in function <Interface\FrameXML\ChatFrame.lua:4266
(tail call): ?
Interface\FrameXML\ChatFrame.lua:4374 in function <Interface\FrameXML\ChatFrame.lua:4332
[C]: in function `ChatEdit_ParseText'
Interface\FrameXML\ChatFrame.lua:4253 in function `ChatEdit_OnTextSet'
[string "*:OnTextSet"]:1: in function <[string "*:OnTextSet"]:1>
[C]: ?
[C]: in function `SetText'
Interface\FrameXML\ChatFrame.lua:3653 in function `ChatEdit_OnUpdate'
[string "*:OnUpdate"]:1: in function <[string "*:OnUpdate"]:1>

Locals: (*temporary) = WIM3_msgFrame1ScrollingMessageFrame {
 0 = <userdata>
 RefreshIfNecessary = <function> defined =[C]:-1
 OnPostShow = <function> defined =[C]:-1
 GetNumVisibleLines = <function> defined =[C]:-1
 ScrollUp = <function> defined =[C]:-1
 SetTimeVisible = <function> defined =[C]:-1
 hasOwnFontObject = true
 OnFontObjectUpdated = <function> defined =[C]:-1
 GetFading = <function> defined =[C]:-1
 Clear = <function> defined =[C]:-1
 shouldFadeAfterInactivity = false
 SetIndentedWordWrap = <function> defined =[C]:-1
 GetTimeVisible = <function> defined =[C]:-1
 GetJustifyV = <function> defined =[C]:-1
 SetFont = <function> defined =[C]:-1
 GetMaxLines = <function> defined =[C]:-1
 BackFillMessage = <function> defined =[C]:-1
 UnpackageEntry = <function> defined =[C]:-1
 FontStringContainer = <unnamed> {
 }
 SetShadowOffset = <function> defined =[C]:-1
 GetFont = <function> defined =[C]:-1
 SetMaxLines = <function> defined =[C]:-1
 timeVisibleSecs = 10
 PageUp = <function> defined =[C]:-1
 RefreshDisplay = <function> defined =[C]:-1
 SetFontObject = <function> defined =[C]:-1
 MakeFontObjectCustom = <function> defined =[C]:-1
 CalculateNumVisibleLines = <function> defined =[C]:-1
 fontObject = table: 0000025B75AF32D0 {
 }
 overrideFadeTimestamp = 0
 SetInsertMode = <function> defined =[C]:-1
 MarkDisplayDirty = <function> defined =[C]:-1
 GetMessageInfo = <function> defined =[C]:-1
 ScrollDown = <function> defined =[C]:-1
 AtTop = <function> defined =[C]:-1
 GetFontObject = <function> defined =[C]:-1
 SetScrollOffset = <function> defined =[C]:-1
 CanEffectivelyFade = <function> defined =[C]:-1
 insertMode = 2
 OnPreSizeChanged = <function> defined =[C]:-1
 GetScrollOffset = <function> defined =[C]:-1
 GetTextColor = <function> defined =[C]:-1
 ResetAllFadeTimes = <function> defined =[C]:-1
 GetSpacing = <function> defined =[C]:-1
 OnPreLoad = <function> defined =[C]:-1
 PackageEntry = <function> defined =[C]:-1
 CalculateLineSpacing = <function> defined =[C]:-1
 SetSpacing = <function> defined =[C]:-1
 isLayoutDirty = true
 ScrollToTop = <function> defined =[C]:-1
 isDisplayDirty = true
 ScrollToBottom = <function> defined =[C]:-1
 AdjustMessageColors = <function> defined =[C]:-1
 GetNumMessages = <function> defined =[C]:-1
 RefreshLayout = <function> defined =[C]:-1
 GetShadowColor = <function> defined =[C]:-1
 parentWindow = WIM3_msgFrame1 {
 }
 fadeDurationSecs = 3
 GetJustifyH = <function> defined =[C]:-1
 OnPostUpdate = <function> defined =[C]:-1
 PageDown = <function> defined =[C]:-1
 GetMaxScrollRange = <function> defined =[C]:-1
 ---------------------------------------------------------------------------------End Prob# 1.
Prob #2 = Lua content:
Message: Interface\AddOns\WIM\Sources\WindowHandler.lua:709 WIM3_msgFrame8ScrollingMessageFrame doesn't have a "OnMessageScrollChanged" script
Time: 10/27/16 12:13:17
Count: 1
Stack: [C]: in function `GetScript'
Interface\AddOns\WIM\Sources\WindowHandler.lua:709 in function <Interface\AddOns\WIM\Sources\WindowHandler.lua:704
Interface\AddOns\WIM\Sources\WindowHandler.lua:1226 in function <Interface\AddOns\WIM\Sources\WindowHandler.lua:788
Interface\AddOns\WIM\Sources\WindowHandler.lua:1367 in function <Interface\AddOns\WIM\Sources\WindowHandler.lua:1317
(tail call): ?
Interface\AddOns\WIM\Modules\ChatEngine.lua:171 in function <Interface\AddOns\WIM\Modules\ChatEngine.lua:160
Interface\AddOns\WIM\Modules\ChatEngine.lua:310 in function `handler'
...s\WIM\Libs\LibChatHandler-1.0\LibChatHandler-1.0.lua:274 in function <...s\WIM\Libs\LibChatHandler-1.0\LibChatHandler-1.0.lua:259
...s\WIM\Libs\LibChatHandler-1.0\LibChatHandler-1.0.lua:326 in function <...s\WIM\Libs\LibChatHandler-1.0\LibChatHandler-1.0.lua:314

Locals: (*temporary) = WIM3_msgFrame8ScrollingMessageFrame {
 0 = <userdata>
 RefreshIfNecessary = <function> defined =[C]:-1
 OnPostShow = <function> defined =[C]:-1
 GetNumVisibleLines = <function> defined =[C]:-1
 ScrollUp = <function> defined =[C]:-1
 SetTimeVisible = <function> defined =[C]:-1
 hasOwnFontObject = true
 OnFontObjectUpdated = <function> defined =[C]:-1
 GetFading = <function> defined =[C]:-1
 Clear = <function> defined =[C]:-1
 shouldFadeAfterInactivity = false
 SetIndentedWordWrap = <function> defined =[C]:-1
 GetTimeVisible = <function> defined =[C]:-1
 GetJustifyV = <function> defined =[C]:-1
 SetFont = <function> defined =[C]:-1
 GetMaxLines = <function> defined =[C]:-1
 BackFillMessage = <function> defined =[C]:-1
 UnpackageEntry = <function> defined =[C]:-1
 FontStringContainer = <unnamed> {
 }
 SetShadowOffset = <function> defined =[C]:-1
 GetFont = <function> defined =[C]:-1
 SetMaxLines = <function> defined =[C]:-1
 timeVisibleSecs = 10
 PageUp = <function> defined =[C]:-1
 RefreshDisplay = <function> defined =[C]:-1
 SetFontObject = <function> defined =[C]:-1
 MakeFontObjectCustom = <function> defined =[C]:-1
 CalculateNumVisibleLines = <function> defined =[C]:-1
 fontObject = table: 0000025B905F3AF0 {
 }
 overrideFadeTimestamp = 0
 SetInsertMode = <function> defined =[C]:-1
 MarkDisplayDirty = <function> defined =[C]:-1
 GetMessageInfo = <function> defined =[C]:-1
 ScrollDown = <function> defined =[C]:-1
 AtTop = <function> defined =[C]:-1
 GetFontObject = <function> defined =[C]:-1
 SetScrollOffset = <function> defined =[C]:-1
 CanEffectivelyFade = <function> defined =[C]:-1
 insertMode = 2
 OnPreSizeChanged = <function> defined =[C]:-1
 GetScrollOffset = <function> defined =[C]:-1
 GetTextColor = <function> defined =[C]:-1
 ResetAllFadeTimes = <function> defined =[C]:-1
 GetSpacing = <function> defined =[C]:-1
 OnPreLoad = <function> defined =[C]:-1
 PackageEntry = <function> defined =[C]:-1
 CalculateLineSpacing = <function> defined =[C]:-1
 SetSpacing = <function> defined =[C]:-1
 isLayoutDirty = true
 ScrollToTop = <function> defined =[C]:-1
 isDisplayDirty = true
 ScrollToBottom = <function> defined =[C]:-1
 AdjustMessageColors = <function> defined =[C]:-1
 GetNumMessages = <function> defined =[C]:-1
 RefreshLayout = <function> defined =[C]:-1
 GetShadowColor = <function> defined =[C]:-1
 parentWindow = WIM3_msgFrame8 {
 }
 fadeDurationSecs = 3
 GetJustifyH = <function> defined =[C]:-1
 OnPostUpdate = <function> defined =[C]:-1
 PageDown = <function> defined =[C]:-1
 GetMaxScrollRange = <function> defined =[C]:-1
 SetJustifyH = <function> defined =[C]:-1
 SetFadeDuration = <function> defined =[C]:-1
 GetShadowOffset = <function> defined =[C]:-1
 GetPagingScrollAmount = <function> defined =[C]:-1
 SetTextColor = <function> defined =[C]:-1
 AtBottom = <function> defined =[C]:-1
 AddMessage = <function> defined =[C]:-1
 SetShadowColor = <function> defined =[C]:-1
 widgetName = "
----------------------------------------------------------------------------End Prob #2

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