Using Windows 7 64-bit, 4GB RAM, and Office Plus 2013, fully updated as of 03/31/2015:

User has multiple Excel windows open, multiple Outlook windows open and multiple Word windows open (4 word docs/windows) -

When the user opens a 5th Word document, a 5th item appears on the taskbar, but it is invisible (just a document outline).  This happened today as a result of a mail merge.  The merge happened, opened the new resulting doc, but was not visible.  We hit the red "X" on the taskbar item to which it asked if we wanted to save.  We did, and then opened the saved doc from her docs directory and it opened fine.  Obviously Word is working but just not showing up.  This seems to happen only when multiple Office items are open.  Is this an Office bug?  User has about 79% RAM in use at the time of this glitch, but never over-subsc

I have been dealing with this for months.  I have to minimize everything and then maximize the outlined document to get it to open.  In Word, this is now happening almost every time I open a second document.... it no longer requires a lot of documents to be open.  I've never had this issue in any other version of office.

I saw your reply on my original post.  I've never found a fix.

Jessica

Hi,

As far as I know, this issue usually occurs with Windows7 and Office 2013. Please try the below methods:

• File - Options - Advanced - General section - check the box for "ignore other apps that use DDE". 
• File - Options- Advanced - Display - uncheck Disable hardware graphics acceleration.
• Update display card driver
• Increase virtual memory (We'd better use more RAM)

Hope it's helpful.

Regards,