Problem installing on localhost

Hi folks,
New boy here; and a bit stuck.

For info, my specs are:
Joomla! 2.5.1
Hikashop Starter (com_hikashop_starter_1.5.6_2012-02-06.zip)

I can't install on localhost; message I'm getting is: "Unable to write entry".

I've successfully installed from the same file to the web server, so I know the zip archive is fine, and I've had no problems with any other extensions (I even installed and removed a few just to check my localhost setup is all ok, which it is).

I've been through the fixes on the support page, but it still won't work. Using the 'fix' that enables better error reporting, the only thing I notice is a change of 'slash' direction in the string when trying to 'Install from Directory'. The error report is as follows:

-1 - An error has occurred.

Copy failed C:\Users\Frank\The Workshop\Websites\DevSERVER_xampp\htdocs\test\tmp\hikashop\back\extensions/plg_hikashoppayment_bf_rbsbusinessgateway/bf_rbsbusinessgateway_configuration.php => C:\Users\Frank\The Workshop\Websites\DevSERVER_xampp\htdocs\Allsites\test\administrator\components\com_hikashop\extensions/plg_hikashoppayment_bf_rbsbusinessgateway/bf_rbsbusinessgateway_configuration.php

Notice the change from '\' to '/' after "extensions". Is that normal? Seems a bit odd to me.

Very grateful for any assistance anyone can offer. As an infant Hikashopper I need, from scratch, to learn the workings of Hikashop and how to integrate it into pages; I would prefer to do so on my local machine rather than across the web.

Hope someone out there can help!
Cheers,
Frank

Thank you Nicolas that was very helpful!

Although we don't know why the problem occurred, the workaround you suggested has done the trick, i.e. I found and grabbed Akeeba (first time user there too; brilliant system and documentation) and created a backup. Now having 'restored' that onto localhost everything's working perfectly. I can start learning Hikashop now

Many thanks again.