this is an i7 machine with 8GB of ram. when very little applications are opened, low RAM usage and low CPU usage, i often get a message from excel saying : "excel cannot complete this task with available resources. choose less data or close other applications".

i am not trying to open any large spreadsheets, sometimes just the first spreadsheet. any ideas ?

Hi Tal Amir,

Which version of Office are you using? 32bit or 64bit?

Based on your error message, I suggest you refer to this KB article and try these methods:
https://support.microsoft.com/en-us/kb/2779852

If you're using 32bit Office, I suggest you test 64bit Office. Beacuse 32bit office you run are limited to making use of only 2GB of RAM. You can get more information about 32bit and 64bit Office from this link:
https://support.office.com/en-sg/article/Choose-the-32-bit-or-64-bit-version-of-Office-2dee7807-8f95-4d0c-b5fe-6c6f49b8d261?ui=en-US&rs=en-SG&ad=SG

Please try these methods and let me know if they work for you, I'm glad to help and follow up your reply.

Regards,

Emi Zhang
TechNet Community Su