I get a lot of the following errors.
What can be the source of this problem?

Product name: Zimbra Desktop
Product version: 7.1.2
Build ID: 10978
Release type: GA
OS Platform: Mac OS X i386 10.6.8
Time of event: 2011-10-06 15:22:50
Error type: zclient.IO_ERROR
Item ID: 1
Error summary: Sync failed due to IOException for the following items
Items will be retried on next sync
Item Id: 1073748129 Message: PushChanges.sync


Failure details - PLEASE REMOVE ANY SENSITIVE INFORMATION
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com.zimbra.common.zclient.ZClientException: /Users/<username>/Library/Zimbra Desktop/store/0/2/msg/1/1073748129-51327.msg (No such file or directory)
ExceptionId:sync-mbox-<email address>:1317907369058:4dadebb2c1dbb10c
Code:zclient.IO_ERROR
at com.zimbra.common.zclient.ZClientException.IO_ERRO R(ZClientException.java:45)
at com.zimbra.cs.zclient.ZMailbox.uploadContentAsStre am(ZMailbox.java:1906)
at com.zimbra.cs.mailbox.PushChanges.uploadMessage(Pu shChanges.java:468)
at com.zimbra.cs.mailbox.PushChanges.syncMessage(Push Changes.java:1212)
at com.zimbra.cs.mailbox.PushChanges.sync(PushChanges .java:303)
at com.zimbra.cs.mailbox.PushChanges.sync(PushChanges .java:193)
at com.zimbra.cs.mailbox.MailboxSync.sync(MailboxSync .java:191)
at com.zimbra.cs.mailbox.ZcsMailbox.sync(ZcsMailbox.j ava:121)
at com.zimbra.cs.mailbox.ZcsMailbox.syncOnTimer(ZcsMa ilbox.java:102)
at com.zimbra.cs.mailbox.SyncMailbox$1.run(SyncMailbo x.java:257)
at java.util.TimerThread.mainLoop(Timer.java:512)
at java.util.TimerThread.run(Timer.java:462)
Caused by: java.io.FileNotFoundException: /Users/<username>/Library/Zimbra Desktop/store/0/2/msg/1/1073748129-51327.msg (No such file or directory)
at java.io.FileInputStream.open(Native Method)
at java.io.FileInputStream.<init>(FileInputStream.jav a:120)
at com.zimbra.common.util.FileUtil.isGzipped(FileUtil .java:146)
at com.zimbra.cs.store.FileDescriptorCache.getSharedF ile(FileDescriptorCache.java:138)
at com.zimbra.cs.store.FileDescriptorCache.read(FileD escriptorCache.java:105)
at com.zimbra.cs.store.BlobInputStream.read(BlobInput Stream.java:278)
at java.io.InputStream.read(InputStream.java:85)
at org.apache.commons.httpclient.methods.InputStreamR equestEntity.writeRequest(InputStreamRequestEntity .java:170)
at org.apache.commons.httpclient.methods.EntityEnclos ingMethod.writeRequestBody(EntityEnclosingMethod.j ava:499)
at org.apache.commons.httpclient.HttpMethodBase.write Request(HttpMethodBase.java:2114)
at org.apache.commons.httpclient.HttpMethodBase.execu te(HttpMethodBase.java:1096)
at org.apache.commons.httpclient.HttpMethodDirector.e xecuteWithRetry(HttpMethodDirector.java:398)
at org.apache.commons.httpclient.HttpMethodDirector.e xecuteMethod(HttpMethodDirector.java:171)
at org.apache.commons.httpclient.HttpClient.executeMe thod(HttpClient.java:397)
at com.zimbra.common.httpclient.HttpClientUtil.execut eMethod(HttpClientUtil.java:55)
at com.zimbra.common.httpclient.HttpClientUtil.execut eMethod(HttpClientUtil.java:41)
at com.zimbra.cs.zclient.ZMailbox.uploadContentAsStre am(ZMailbox.java:1896)
... 10 more

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