I'm very pleased with the Sonar X1 Studio program, but it's not perfect. Vsti:s has started to disappear from both of my computers. The other is a laptop with Vista, 32 bit. The other is a desktop computer with Windows 7, 64 bit. Synths that can't be used anymore include Oatmeal, Analog Player and Rapture LE. They are all visible in the Cakewalk Plug-in Manager place, but when I try to insert them I can't see them when I try to insert them. I have reinstalled the synths (except Rapture and Analog player ), but it didn't help. I don't want to install Sonar again because I fear that something happens and I can't use Sonar anymore. I have over 200 vsti:s.
kakku

There is a limit to how many plug-ins will fit in the X1 menu system. Here is similar thread http://forum.cakewalk.com/FindPost/2266679 X3 addressed the plug-in limit issue.

Thank you for your tip scook. However I didn't find in that thread anything that would help me with my problem. I have done a custom list for my plugins where there are about 20 synths. And in this list or any list I can't find the missing synths. 
kakku

Now it seems the problem has been kind of solved. I played with the options in the cakewalk plug-in manager and it started crashing when I did the vst scan. Then I put the default settings on again in the options place and did a vst scan again and it crashed again. But the good news is I got other synths back, except Oatmeal which has a nice bass sound iirc. In case someone wants to see the error codes:
 
 Before crashing there was a Code 7, but it didn't crash yet.
 
Cakewalk vst scan has stopped working
 
Problem Event Name:    APPCRASH
  Application Name:    VstScan.exe
  Application Version:    5.0.2.0
  Application Timestamp:    4f4fbdd0
  Fault Module Name:    StackHash_fed5
  Fault Module Version:    6.1.7601.18247
  Fault Module Timestamp:    521ea8e7
  Exception Code:    c0000374
  Exception Offset:    000ce753
  OS Version:    6.1.7601.2.1.0.768.3
  Locale ID:    1035
  Additional Information 1:    fed5
  Additional Information 2:    fed55c7042fdb4d25c09220f17484eb0
  Additional Information 3:    ec62
  Additional Information 4:    ec62d330fcf3022d48722cafba81c589

second try

Application Name:    VstScan.exe
  Application Version:    5.0.2.0
  Application Timestamp:    4f4fbdd0
  Fault Module Name:    StackHash_59bf
  Fault Module Version:    6.1.7601.18247
  Fault Module Timestamp:    521ea8e7
  Exception Code:    c0000374
  Exception Offset:    000ce753
  OS Version:    6.1.7601.2.1.0.768.3
  Locale ID:    1035
  Additional Information 1:    59bf
  Additional Information 2:    59bf358a760423b3da9ae9bb438b07d4
  Additional Information 3:    ee02
  Additional Information 4:    ee0293bc20dc87713d720f5b60dc4c78

third time

Problem Event Name:    APPCRASH
  Application Name:    VstScan.exe
  Application Version:    5.0.2.0
  Application Timestamp:    4f4fbdd0
  Fault Module Name:    StackHash_39ff
  Fault Module Version:    6.1.7601.18247
  Fault Module Timestamp:    521ea8e7
  Exception Code:    c0000374
  Exception Offset:    000ce753
  OS Version:    6.1.7601.2.1.0.768.3
  Locale ID:    1035
  Additional Information 1:    39ff
  Additional Information 2:    39ff68b14df44533ca3b7be85156550f
  Additional Information 3:    a1be
  Additional Information 4:    a1be9f8c15cf2cfb310a2c22c710021f
 
kakku

Almost funny. Now that I got most of my synths back I tried to get Oatmeal back too by vst scanning again. What happened is now I lost again some of my favorite synths...
 
Update:did a couple more vst scans and now only oatmeal is missing.
kakku

Has Oatmeal been updated since it was introduced in 2006? Seems like it's crashing VST scan. I went to the Fuzpilz page and it doesn't exist...seems like the only version kicking around the web is pretty ancient.
 
If all else fails, Sonar includes some fine synths for subtractive bass sounds. 

Thank you Anderton for the tip and for checking the Oatmeal status. There sure is some nice bass sounds in the Sonar itself, but I liked the Oatmeal's bass sound a lot. But better forget the Oatmeal, it's ancient history.
kakku

This tends to be an issue with free plug-ins, because there's no incentive to update to accommodate changes in operating systems and computers. Of course some companies do, but some plug-ins just exist for a moment in time and then...disappear.

If you move the crash message window aside, rather than closing it, the vst scanner will still be showing the dll it crashed on
Hth

Thank you lawp for your tip. I did move the crash message window aside and a couple of times it showed some vst's name. Then sometimes it does not show any vst's name. At the moment I'm afraid to press the vst scan button because I fear that I lose some vst synths or effects.
kakku