I use trial version v3.8.8 The problem has occured when I click
New project expert option >> Enter backlinks manually

I put around 5,000 domains and check only Domain PageRank then click next to run process but It seem program stuck or wait a long time for program start process.

How can I slove this problem ??

If the problem occurs again, please locate the log file right after:

http://www.link-assistant.com/support/i ... 4&nav=0,15

Then send it to us as an attachment in a ticket ( www.link-assistant.com/support ) - we'll be able to tell you how to avid that.

At the first glance, however, I would suggest adding links in smaller portions, this might be lighter on your system...