Hello,
Are you receiving any errors from SEP client, if that is causing the issue to occur?
Can you check in SEP logs, if you have any logs logged?
I hope you have applied all the MS Office patches on the machines?
Office 2007 was tested and qualified for GEM.
The root cause of any problems you are seeing is likely with some plugin that is being used.
We would like to investigate this some more.
Please open a support case so that our engineers can collect the relevant data.