Joomla 2.5.1, JMS 1.2.78.

All templetes deploy fine in standaone Joomla 2.5.1
Some templates produce "An error had occured. Copy failed" in slave.

Error log:

[error] [client 10.10.1.1] PHP Notice: Only variable references should be returned by reference in /var/app/wjl/administrator/components/com_multisites/libraries/joomla/installer/installer_multisites.php on line 115, referer: prcdev.ellisdon.com/administrator/index....option=com_installer

Are there compatibility issues for templates?

First, if you use a Joomla 2.5 version, we recommend that you use the latest JMS version.
See the FAQ for the procedure to get the latest version.
www.jms2win.com/en/faq/faq-joomla-multi-sites#cat-122

Second, PHP Notice are not errors.
This is just a notice that is reported by PHP that are related to PHP compatibilities and sometimes also due to change perform in Joomla version that removed some reference.
They are not errors.

Concerning the "Copy failed", as you can read plenty of times in the forum, this might be due to a problem of permission.
So verify that the files can be updated.

We already tried chmod -R 777 on the source directory. No luck.

Also, the same source directory copied to a independent joomla installation works perfectly.

Other templates deployed fine which indicate that the destination permission is OK.

Get more info on the "copy failed" returned by joomla is not something provided by Joomla. So you have to try adding debug trace information yourself inside Joomla to get more info on the file and the reason.

I can not tell you more.
All the time that we encountered such "copy failed" that was due to a permission error.

If you want that we help you debug joomla to get more info on the file (or directory) that cause the "copy failed", this is possible with our billable support that you can order at
www.jms2win.com/en/joomla-multisite?page...35&category_id=1