phpmyadmin hanging on database import (no replies)

Hi there folks. Until recently my WAMPServer install has worked perfectly. Recently I've become unable to import databases through phpMyadmin; they are not large (766k in the most recent case) and shouldn't be hitting any kind of upload limit, but MyAdmin hangs and becomes unresponsive whenever I try.

I'm able to perform all other functions in MyAdmin so far, but as soon as I try to import an .sql or .sql.gz file, MyAdmin hangs with a "waiting...." message and "waiting for localhost" at the bottom of the browser (both Chrome and Firefox).

It worked briefly earlier this week, but is now back to not responding.I've rebooted WAMPServer and my Windows machine a number of times.

Thanks for anything you can suggest.

Here's my config:

Win7Pro, Service Pack 1, 64 bit
WampServer Version 3.0.6 64bit
Apache 2.4.23 - PHP 5.6.25 - MySQL 5.7.14
PHP 5.6.25 for CLI (Command-Line Interface)

6 - What color is the WampServer icon (in the notification area of the taskbar)

Green

d - The windows event viewer

No messages


7 - In the file c:\Windows\System32\drivers\etc\hosts, what are the active lines with the name [localhost] in them?

127.0.0.1 localhost
::1 localhost


If the WampServer icon is green:

8 - Do you have access to localhost (Homepage WampServer)?

Yes


8a - If so, is there an error message at the bottom of the page?

No

9 - Do you have access to phpMyAdmin?

Yes

10 - If you refer to an error message, please include the EXACT wording of the error in your post

No

11 - If you use an Antivirus and / or Firewall, please include the names of these

Avast Internet Security


12 - What is the full path to the installation of WampServer (eg D:\wamp\)

C:\wamp64


13 - If you have one or more Virtual Hosts defined, please show their definition(s)

# Virtual Hosts
#

<VirtualHost *:80>
ServerName localhost
DocumentRoot c:/wamp64/www
<Directory "c:/wamp64/www/">
Options +Indexes +Includes +FollowSymLinks +MultiViews
AllowOverride All
Require local
</Directory>
</VirtualHost>
#
<VirtualHost *:80>
ServerName stripfixrevamp
DocumentRoot "c:/wamp64/www/stripfixrevamp"
<Directory "c:/wamp64/www/stripfixrevamp/">
Options +Indexes +Includes +FollowSymLinks +MultiViews
AllowOverride All
Require local
</Directory>
</VirtualHost>

<VirtualHost *:80>
ServerName spotartcatalog
DocumentRoot "c:/wamp64/www/spotartcatalog"
<Directory "c:/wamp64/www/spotartcatalog/">
Options +Indexes +Includes +FollowSymLinks +MultiViews
AllowOverride All
Require local
</Directory>
</VirtualHost>

<VirtualHost *:80>
ServerName hybridwho
DocumentRoot "c:/wamp64/www/hybridwho"
<Directory "c:/wamp64/www/hybridwho/">
Options +Indexes +Includes +FollowSymLinks +MultiViews
AllowOverride All
Require local
</Directory>
</VirtualHost>

<VirtualHost *:80>
ServerName whoswho
DocumentRoot "c:/wamp64/www/whoswho"
<Directory "c:/wamp64/www/whoswho/">
Options +Indexes +Includes +FollowSymLinks +MultiViews
AllowOverride All
Require local
</Directory>
</VirtualHost>

<VirtualHost *:80>
ServerName bibliography
DocumentRoot "c:/wamp64/www/bibliography"
<Directory "c:/wamp64/www/bibliography/">
Options +Indexes +Includes +FollowSymLinks +MultiViews
AllowOverride All
Require local
</Directory>
</VirtualHost>