I use Limesurvey 1.92+ 120822 and when I want to open the Expression Manager it gives me only an empty / blank page in different browsers and even the source code is empty.
How can I fix that?
I have no access to the server, only to Limesurvey backend so I don't know which database or OS is used.

This might be a permission problem accessing some directory or directories (maybe ./scripts and/or ./classes/expressions).
If this is running on Linux (e.g. Ubuntu Server v12.04 LTS) with Apache2 an administator should look into the file '/var/log/apache2/error.log'.
There the access problems should be listed.

Hi
Did you find a solution to solve your Expression Manager error ?
I face the same issue, and would be interresed to get a solution to fix it.
I've checked the apache error.log file but could not found any trace or error message.

No, not yet

I made further tests and I realized that I was able to access the Expression Manager using the admin user. I then changed my user rights to add super-admin right and now it works. So, it seems to be linked to user right ... You should check your account right and see if it solves the issue.

Thisis strange, I have never heard that the Expression Manager usage depends on user rights.
Can anyone confirm this?

Expression Manager does not depend upon user rights. You can run any survey that happens to include Expression Manager-based branching / tailoring / validation without needing to be logged in.

However, the EM button that lets you access the list of available functions, unit tests, and administrative tools (like bulk converting conditions to relevance) does test user permissions. Is that the problem people are running into? If so, we could adjust permissions accordingly (e.g. anyone who can author an instrument can see the list of functions and unit tests; but only administrators can do the bulk conversions).