I spent a lot of time with SE support on the phone with an install of the latest (2.10.46) version of PC suite.
I eventually removed .Net from the PC, and PC Suite worked.

Even though the Suite was 2.10.46, it was showing on my system as 2.10.37 (or similar) and just did not want to work with my handset.

Try this...
1. Remove PC Suite
2. Remove .NET
3. Reinstall PC Suite
4. Try connecting a few times, see if it works consistently.
5. Reinstall .NET
6. Try connecting again, and again see if it works consistently.

hth