First you restart your sever. Then check again. I hope it is patched with latest OS and Exchange patches. If restart doesn't fix it. You can recreate the index again. However it can take time to complete. If DB size is huge. Better do it during weekend.
1. Try registering "msfte.dll" (Should be in Bin folder) and then restart Search
services (MS Exchange search Indexer and Microsoft Search)
2. If above don't work then ran repair of msfte.exe (Microsoft Full Text Indexing
Engine for Exchange) from SP1dump\serverroles\mailbox
Right clicked MSFTE.EXE and select REPAIR
Restart search services, Now Catalog folders should get created
3. Give ample time to generate indexing files. (It may take upto 24 hours). Once
the file genratation completes OWA search should be good.
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